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                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                            ------------------------

                                  FORM 10-K/A

(MARK ONE)
[X]   ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
      SECURITIES EXCHANGE ACT OF 1934

                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000

                                       OR

[ ]   TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
      SECURITIES EXCHANGE ACT OF 1934

        FOR THE TRANSITION PERIOD FROM                TO

                        COMMISSION FILE NUMBER 000-25943

                           JUPITER MEDIA METRIX, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

<Table>
<S>                                            <C>
                   DELAWARE                                      11-3374729
       (STATE OR OTHER JURISDICTION OF                        (I.R.S. EMPLOYER
        INCORPORATION OR ORGANIZATION)                      IDENTIFICATION NO.)

          21 ASTOR PLACE, 6TH FLOOR                                10003
                 NEW YORK, NY                                    (ZIP CODE)
   (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)
</Table>

                                 (212) 780-6060
              (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE)

       SECURITIES TO BE REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:

<Table>
<Caption>
TITLE OF EACH CLASS  NAME OF EACH EXCHANGE ON WHICH REGISTERED
-------------------  -----------------------------------------
<S>                  <C>
       None
</Table>

       SECURITIES TO BE REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:
                     Common Stock, par value $.01 per share

     INDICATE BY CHECK MARK WHETHER THE REGISTRANT: (1) HAS FILED ALL REPORTS
REQUIRED TO BE FILED BY SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF
1934 DURING THE PRECEDING 12 MONTHS (OR SUCH SHORTER PERIOD THAT THE REGISTRANT
WAS REQUIRED TO FILE SUCH REPORTS), AND (2) HAS BEEN SUBJECT TO SUCH FILING
REQUIREMENTS FOR THE PAST 90 DAYS.  YES [X]  NO [ ]

     INDICATE BY CHECK MARK IF DISCLOSURE OF DELINQUENT FILERS PURSUANT TO ITEM
405 OF REGULATION S-K IS NOT CONTAINED HEREIN, AND WILL NOT BE CONTAINED, TO THE
BEST OF REGISTRANT'S KNOWLEDGE, IN DEFINITIVE PROXY OR OTHER INFORMATION
STATEMENTS INCORPORATED BY REFERENCE IN PART III OF THIS FORM 10-K OR ANY
AMENDMENT TO THIS FORM 10-K.  [X]

     As of March 15, 2001, there were 35,434,655 shares of the registrant's
Common Stock, $.01 par value, outstanding, and the aggregate market value of the
voting stock held by non-affiliates of the registrant was $127,137,028 (based on
the last reported sale price on the NASDAQ National Market on that date).

                      DOCUMENTS INCORPORATED BY REFERENCE

     Certain portions of the registrant's definitive proxy statement for the
annual meeting of stockholders to be held May 16, 2001, which will be filed with
the Commission subsequent to the date hereof pursuant to Regulation 14A of the
Securities Exchange Act of 1934, are incorporated by reference into Part III of
this report.
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<PAGE>

     INTRODUCTORY NOTE The purpose of this Form 10-K/A is to restate the
consolidated financial statements of Jupiter Media Metrix, Inc. for the year
ended December 31, 2001. In a press release issued on February 11, 2002, the
Company announced that approximately $5.7 million which previously was reflected
as current assets should have been reflected as restricted cash and other
assets. As previously disclosed by the Company, the restricted cash represents
amounts collateralizing letters of credit issued in lieu of cash security
deposits under the Company's real estate leases. The financial statements
included in this Form 10-K/A have been restated to reflect the change in
presentation.

THIS REPORT CONTAINS FORWARD-LOOKING STATEMENTS BASED ON OUR CURRENT
EXPECTATIONS, ASSUMPTIONS, ESTIMATES AND PROJECTIONS ABOUT JUPITER MEDIA METRIX
AND OUR INDUSTRY. THESE FORWARD-LOOKING STATEMENTS INVOLVE RISKS AND
UNCERTAINTIES. OUR ACTUAL RESULTS COULD DIFFER MATERIALLY FROM THOSE ANTICIPATED
IN SUCH FORWARD-LOOKING STATEMENTS AS A RESULT OF CERTAIN FACTORS, AS MORE FULLY
DESCRIBED IN THIS SECTION AND ELSEWHERE IN THIS REPORT. JUPITER MEDIA METRIX
UNDERTAKES NO OBLIGATION TO UPDATE PUBLICLY ANY FORWARD-LOOKING STATEMENTS FOR
ANY REASON, EVEN IF NEW INFORMATION BECOMES AVAILABLE OR OTHER EVENTS OCCUR IN
THE FUTURE.

                                     PART I

ITEM 1.  BUSINESS

INTRODUCTION

     Jupiter Media Metrix, Inc. is a global provider of innovative and
comprehensive research and measurement products and services that analyze the
impact of the Internet and new technologies on commerce and marketing. Our
business units include Media Metrix, Jupiter Research, AdRelevance and Jupiter
Events. Media Metrix offers clients a broad range of products and services that
collect audience data and measure new media usage on the Internet and other
digital media. Jupiter Research provides business-to-business and
business-to-consumer clients with strategic analysis and insights, including
industry trends, forecasts and best practices, all backed by proprietary data.
AdRelelvance specializes in the automated retrieval and delivery of online
advertising data. Jupiter Events hosts conferences focusing on the global
digital economy.

     All of our products and services are designed to assist companies in making
critical business decisions and in utilizing Internet technologies to more
effectively operate their businesses. Clients utilize our research and data
products to define business opportunities and competitive threats; analyze
technology adoption and usage; prioritize new business initiatives; identify
potential partners and alliances; evaluate and manage vendors; buy, sell and
plan advertising; and track audience behaviors. We have a highly diversified and
global client base, including large and small companies in the media,
technology, financial services, advertising, consumer products, retail, travel
and professional services industries. As of December 31, 2000, we had over 2,300
client contracts for our research and measurement products. We provide our
research and measurement products primarily through annual subscriptions, and we
currently deliver our products primarily over the Internet.

     We have rapidly expanded our business outside the United States in order to
establish our products as the global standard for digital media measurement and
to become the premier worldwide resource for analysis of the Internet economy.
We believe our Media Metrix products currently provide data covering over 90
percent of Internet usage worldwide and our Jupiter Research products currently
provide analysis on the top Internet commerce markets as measured by the total
number users. We currently manage panels in 14 countries and conduct research
covering 16 countries. In many of these countries and regions, we have aligned
ourselves with the leading media research and marketing information service
companies. These alliances provide us with industry information, client
prospects, research and panel expertise, as well as public relations and
marketing initiatives.

     Our principal executive offices are located at 21 Astor Place, New York,
New York 10003, and our telephone number is 212-780-6060. Jupiter Media Metrix,
Jupiter(R), Media Metrix(R), MMXI, JMXI, PC Meter, RelevantKnowledge, e-Trends,
The Power of Relevant Knowledge, MyMetrix, AdRelevance, JxNetworks and the
Jupiter Media Metrix logo are trademarks of Jupiter Media Metrix. Any other
trademark, trade name or service mark of any other company appearing in this
document belongs to its holder.
                                        1
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PRODUCTS, SERVICES AND METHODOLOGY

     Our measurement and research products and services are designed to enable
companies to make intelligent business decisions about Internet commerce and
consumer and business use of the Internet and related technologies.

  Audience Measurement Products and Services

     Our principal audience measurement products and services are derived from
data collected from our panels and stored in our core databases, which we use to
produce our syndicated and custom Internet audience measurement reports and
services. The Jupiter Media Metrix panel is a high quality, representative
sample of personal computer users, including at-home and at-work users. We
recruit panelists by random digit dial (RDD) telephone solicitation. We also use
direct mail to reach individuals within the RDD sample frame. The panel
currently consists of over 50,000 individuals under continuous measurement in
the United States and over 50,000 individuals under continuous measurement
beyond U.S. borders. In connection with our panel recruitment process, each
panelist is required to fill out a detailed questionnaire, providing background
demographic information including age, gender, household income, geographic
location, level of education, size of household and job classification.

     Our proprietary metering system, or meter, is a software application
installed on a panelist's personal computer. It monitors activity of the
personal computer's operating system and browser. The meter passively records
what users do on their personal computers on a second-by-second basis,
including:

     - the start and stop time of each activity;

     - the application in use;

     - detailed usage activity for proprietary online services; and

     - page-by-page viewing on the Internet.

     We collect the data we need for our products and services without any
agreement or arrangement with operators of Web sites or operators of proprietary
online services like America Online. Because we measure our panelists' computer
usage and not activity at a particular Web site or proprietary service, no
agreements with the operators of Web sites or online services are necessary.

     We began introducing a new version of our metering software in August 1999.
The new meter captures additional details of Internet usage to accurately report
audience behavior of emerging media such as streaming audio and video. This
version also provides real time transmission of data on usage. Our audience
measurement operations worldwide currently use the new meter. The latest version
of our meter also allows us to automatically update the software via the
Internet, with no action required on the part of our panelists. We also collect
data via questionnaires distributed through direct mail and over the Web. We
utilize our own software to collect information on hardware configurations and
software installations of our panelists.

     The statistical quality of the information that we collect is a function of
minimizing both sampling error and measurement error. Sampling error is a
function of the size and quality of the sample. Measurement error is a function
of the scope of the universe under measurement and the quality of our meter for
comprehensive data collection. We minimize sampling error by maintaining a large
panel. We minimize measurement error by measuring all Internet usage, including
the Web, proprietary online services, like America Online, and all other
activity on our panelists' personal computers.

     Once the meter has collected the data from a panelist's personal computer,
data are transmitted to our offices for processing via automatic transfer over
the Web. Data are then combined with those of all the other panelists. The data
are then used to construct several databases, which we use to provide our
reports. We deliver our reports in one or more of the following formats: via
proprietary Web-based delivery systems; e-mail; computer disk or hard copy.

                                        2
<PAGE>

     Our current syndicated audience measurement product offerings consist of
the following:

     - Digital Media Ratings.  Our syndicated audience measurement product
       contains several components. Key Measures provides measures, such as
       unique visitors and visitor demographic information, for all reportable
       Web sites categorized within major sectors. Trends provides information
       on trends within the major sectors in a Key Measures report over six
       month and three month periods. Finally, Online Services provides
       measurement of audience usage of and audience demographics for
       proprietary online services, like America Online or ICQ.

     - Local Markets.  We track national and local market reach, demonstrating
       how national and local Web sites perform within each of the 38 top local
       markets.

     - Consumer Commerce.  Our Q-Metrix Report provides information linking our
       metered Internet usage behavior to consumer media habits, product and
       service usage, lifestyle characteristics and demographics including
       banking and credit card activity, Internet shopping behavior, television
       viewing habits and hobbies. The Online Shopping Report tracks online
       shopping activities across more than 500 Internet sites within 18
       categories, as well as the AOL Shopping Channel. Key measures include the
       number of repeat shoppers and the number of engaged shoppers, defined as
       shoppers who spend more than three minutes on a Web site. Shopper
       Referral Reports are custom reports on the sites that are delivering
       engaged shopper traffic to other sites.

     - Technology.  We produce HardScan, SoftScan and SoftUsage Reports to
       provide details on hardware ownership, peripheral ownership, branding
       information, installed applications and system software, including
       Internet browsers and use of software applications. Additionally, the
       analyses contained in our Linkage Reports and U.S. Consumer PC Report
       provide a unique look at the relationships between hardware, software,
       media, ownership and usage.

     - Ad Networks.  We provide detail on reach, frequency and demographic
       information across ad sales networks and other ad-supported networks like
       DoubleClick, 24/7 Media, Flycast, LinkExchange and AdSmart. The measures
       reported include the full network reach and reach of those Web pages
       where ads have been served.

  Research Services

     Our research services provide our clients with a wide range of proprietary
research, data and advisory analysis and are structured as continuous analytical
services. We have designed our research services to enable clients to make
intelligent business decisions about Internet commerce and consumer and business
use of the Internet and related technologies. These research products and
services define business and strategic goals, identify revenue opportunities,
evaluate business models, analyze marketing strategies, assess enabling
technologies and provide advice on organizational structures and vendor
selections.

     A key component of our research services is access to our research analysts
for discussions and debate related to their research topics. Our clients
typically seek advice or have questions regarding new business or marketing
initiatives, best practices, new opportunities or competitive threats, market
forecasts and/or the value of mergers and strategic partnerships. Clients may
submit issues or questions initially to our dedicated client inquiry staff via
telephone or e-mail. The client inquiry staff, which consists of trained
research professionals who are familiar with all of our research products and
services, coordinates the responses and actively manages access to the analysts.
Based on their subscription level, clients will receive access to our analyst
reports; password-only access to current research and a full-searchable archive;
access to our research analysts for discussion, debate and additional advice;
the ability to participate in customized presentations by our leading analysts;
and conference passes. Clients may access our research analysts or may purchase
our research reports separately.

     We continually evaluate the market demand for additional research services.
We also seek out and receive input from our research analysts, the sales
representatives who are in constant contact with existing and potential clients
and our marketing staff as to the demand for specific research and our ability
to provide

                                        3
<PAGE>

coverage. We also examine a variety of empirical data, including breadth of
applicability, uniqueness of the offering, competitive value and ease of
communication.

     Our research services are generated by a skilled team of research
professionals, including research analysts and an independent data research
group, as well as additional support staff to handle client inquiries. As of
March 15, 2001, we employed a total of 143 research professionals, including 78
analysts. The knowledge and experience of our research professionals,
particularly our analysts, are the crucial elements in our ability to provide
high-quality, timely and original research. Our analysts have extensive industry
experience and varied backgrounds. We recruit them from a number of different
industries, including management consulting and research firms, financial
services, publishing, entertainment and advertising. We believe that the diverse
backgrounds and experiences of our analysts allow us to provide original and
prescriptive research and analysis which frequently challenges the conventional
wisdom and viewpoints promoted by others.

     Our research methodology enables us to deliver compelling, data-driven and
timely analysis across all of our research services. We support our research
professionals with in-house primary research tools and proprietary databases.
Our dedicated data research group delivers innovative survey design, sample
building and data weighing and processing. This group provides each of our
reports with rigorously tested hypotheses that yield action-oriented analysis.
Our data analysis employs a wide set of data-gathering tools, including the
following:

     - Market Forecasting.  We build complex econometric models to capture
       current online activity and forecast user participation, costs and
       revenue. These models define key growth levers, market drivers and market
       inhibitors, providing clients with a clear analytical framework for
       considering upcoming changes in their business sector.

     - Primary Consumer Research.  We conduct our primary research in alliance
       with The NPD Group, Inc., a leading provider of market research. By
       accessing an NPD panel of approximately 600,000 online households, we
       regularly contact consumer households to assess technology trends. In
       addition, we regularly commission research surveys and conduct research
       surveys throughout the world.

     - Customer Valuation Models.  Our analysts construct scenario-driven models
       for measuring the lifetime value of interactive consumers. These models
       provide our analysts with the necessary information to make
       recommendations and assist clients in identifying the ultimate value in
       acquiring and retaining visitors and customers.

     - Operational Benchmark Models.  We develop models that determine the
       current and future costs, infrastructure needs, visit capacity,
       transaction volume and other operational metrics required to manage
       expected user demand. These models measure forecasted operational
       benchmarks for the industry and individual Web sites to help clients
       appropriately invest in building their interactive technology
       infrastructure.

     - Executive Surveys.  We conduct dozens of formal surveys each year with
       top industry executives to explore their strategies, attitudes and
       intentions. These surveys evaluate industry trends and changes and
       provide our analysts with an important measure against which to test
       assumptions and hypotheses.

     - Web Site Functionality Data.  Our analysts use WebTrack, a
       Jupiter-developed database, to measure the performance of various Web
       technologies and site features. Based on systematic quarterly research on
       nearly 300 consumer Web sites, WebTrack provides an overview of the
       distribution of technology services, content and functionality among
       these sites.

     - Case Studies.  Through extensive interviews with industry executives,
       analysis of public documents and secondary research, we compile hundreds
       of case studies each year. These studies identify the strategic
       direction, strengths and weaknesses and key partnerships of major
       Internet commerce companies.

     All of our research products are subject to a stringent editorial and
review process to ensure that every report is accurate, well-written and useful
to our clients. We maintain consistency among the formats of our
                                        4
<PAGE>

research reports across our research services so as to ensure clarity and
readability by all of our clients. Each research topic is first subject to a
series of discussions and meetings to define the scope of the topic, assess the
relevance and importance of the research and highlight key themes and questions.
Prior to publication, each research report is subject to ongoing review and
comment from other analysts and research management.

  New Products and Services

     As a result of our merger with Jupiter Communications, Inc. in September
2000, the full spectrum of our proprietary audience measurement data is now
analyzed by our Jupiter Research analysts to provide analysis and insights into
the particular issues that companies face as the Internet transforms the markets
in which they operate. These services are available to subscribers of our core
research or measurement products and provide detailed measurement and commercial
data, industry forecasts and benchmark studies to make key business decisions in
a particular industry or competitive environment covering the automotive,
banking, brokerage, consumer packaged goods, entertainment, health, music,
retail and travel industries.

     In addition, we are now able to bundle our measurement and research
products and services to enable our clients to develop effective business
strategies and improved decision making. For example, we have recently begun to
bundle our advertising and marketing products to provide marketing and branding
analyst research with our online advertising tracking service. We believe these
enhanced product offerings and services will enable us to provide greater value
to our existing customers and will help us to attract new customers.

  Global Services

     Our global services products are available to subscribers of our core
research or measurement products. We currently produce and develop research
services and products with respect to the following countries and regions:
Canada, Denmark, Finland, France, Germany, Italy, Japan, Latin America, Norway,
Spain, Sweden, and the United Kingdom, and we maintain measurement panels in
Argentina, Brazil, Canada, Denmark, France, Germany, Italy, Japan, Norway,
Spain, Sweden, Switzerland and the United Kingdom. These services identify
market opportunities, competitive dynamics and consumer online behavior in
various countries and regions. A critical component of these services are the
consumer survey data and market forecasts that provide both domestic and foreign
corporations the region-specific measurement and analysis required to make
global strategic planning decisions.

  Advertising Measurement Products

     We offer advertising measurement products and services through our
AdRelevance subsidiary. AdRelevance tracks competitive online advertising and
advertiser data for eight broadly defined categories including automotive,
computer hardware, computer software, telecommunications, financial services,
travel, eRetailing and ePublishing. We currently report on over 340,000 unique
advertisements and 30,000 advertisers.

     The AdRelevance technology systematically and continuously searches
commercial Web sites and captures detailed data about advertising banners,
promotions, sponsorships, text links and rich media. AdRelevance's intelligent
agent technology searches over 5,000,000 URL's daily and continuously evaluates
more than 500,000 unique web pages to provide in-depth advertising tracking
information. Once captured, the data are warehoused, classified and
statistically analyzed.

     By using the AdRelevance technology, our customers can query the
AdRelevance database and generate Web-based reports on demand. This enables
customers to monitor competitors' marketing activities, plan more effective
online campaigns and evaluate campaigns in real time. Customers can gain access
to up-to-date intelligence about their competitors' online marketing
communications programs, enabling them to quickly and easily compare and report
information by a wide range of criteria including advertiser, product, message,
type, industry, location, technology and creative content.

                                        5
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  Events and Conferences

     We produce a wide range of conferences which provide comprehensive coverage
of issues relating to Internet commerce. These conferences offer senior
executives the opportunity to hear first-hand the insights of our analysts and
the leading decisionmakers in the Internet and technology industries. Our
events, which typically run for two to three days, provide an excellent
opportunity to showcase our research and measurement products to current and
potential clients, increase the public profile of our research analysts,
generate favorable press and otherwise promote the Jupiter Media Metrix brand.
Since approximately 70% of the attendees at our conferences are not clients of
our research products and services, these events provide a unique opportunity to
promote our research products and services to potential customers. Our
conferences attract (i) individual attendees, (ii) sponsors, which display their
logo in our conference program and/or host a reception, and (iii) exhibitors,
which receive a booth to promote their companies.

  Customized Services, Reports and Analysis

     We leverage our vast database of information on Internet usage and
technology usage to provide clients with a broad range of special measurement
services, reports and analyses, including vertical market reports, site
retention analyses, usage reports, site content reports, personal clickstream
reports, traffic referral reports and site interaction reports.

     We also provide special research products and services to clients,
including customized research reports. We publish individual research reports
that are available for purchase through direct mail or on our Web site. Sales of
these studies are an important way to expose new companies and executives to our
research.

     Additionally, we perform customized, client-focused research projects
relating to Internet commerce on a limited basis. These projects allow our
clients to take advantage of the knowledge and experience of our research
analysts and to develop structured, detailed responses to specific issues
relevant to their business. Custom studies often form the basis to explore a new
research service and, like our individual research reports, are an effective way
to expose new companies and executives to our research products and services.

INTERNATIONAL OPERATIONS

     We believe that the ability to offer our measurement services and research
products, as well as our Internet conferences, outside of the United States will
be a critical element in the Internet measurement, analysis, intelligence and
events markets. Having established our business models in the United States, we
have continued to develop our international positioning.

     We have entered into a joint venture with two of the leading European media
research and marketing information services companies, GfK AG (based in Germany)
and Ipsos S.A. (based in France), to form MMXI Europe B.V. In connection with
our acquisition of MMXI Nordic, Observer AB (formerly known as SIFO Group AB)
(based in Sweden) became a shareholder in MMXI Europe. Under the umbrella of
MMXI Europe, we have formed subsidiaries in each of the United Kingdom, France,
Germany, Italy and Spain. Additionally, we have entered into a technology
agreement under which we have contributed our technology to MMXI Europe for use
in Europe, excluding Sweden, Denmark, Norway and Finland. Along with GfK and
Ipsos, we also provide certain management services to MMXI Europe and each
subsidiary of MMXI Europe.

     As described above, we completed the acquisition of the Internet audience
measurement business operated by Observer AB in Sweden. The business has been
operated pursuant to a license between us and Observer entered into in 1998
covering Sweden, Norway and Finland. The new company, MMXI Nordic, measures
Internet audiences in Sweden, Norway, Finland and Denmark as a wholly owned
subsidiary of Jupiter Media Metrix. As a part of this acquisition, we also
acquired the site-centric measurement business operated by Observer, known as
NetCheck. We have granted MMXI Europe an option to purchase MMXI Nordic from us
at a future time.

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     We have also entered into joint ventures with:

     - Market Intelligence Corporation (based in Tokyo, Japan) to own and
       operate Jupiter Media Metrix K.K. in Japan;

     - ComQUEST Research, Inc., a wholly owned subsidiary of BBM Bureau of
       Measurement, an industry co-operative owned by Canadian broadcasters,
       advertisers and advertising agencies, to launch Media Metrix Canada;

     - IHA Institut fur Marketanalysen, an affiliate of GfK, to form MMXI
       Switzerland GmbH, a Swiss company, where we, through MMXI Europe, have an
       option to purchase up to an additional 15% of the outstanding equity of
       MMXI Switzerland from IHA which expires December 31, 2003; and

     - Ipsos to form JMXI Latin America B.V., a Netherlands company, which will
       operate our business in Brazil currently run by Media Metrix Brasil Ltda.

     We have also recently granted an exclusive license to AMR Interactive Pty.
Ltd. to operate the Jupiter Media Metrix business in Australia and New Zealand.

     In connection with the formation of each of our international joint
ventures, we granted each of our joint venture partners an option, subject to
certain conditions, to exchange such partners shares in the respective joint
ventures for shares of our common stock. If any partner elects to exercise its
option to convert its shares into shares of our common stock, we will need to
record additional goodwill in an amount equal to the difference between the then
fair market value of the shares of our common stock multiplied by the number of
shares issues and the net book value of the joint venture of which such partner
is a shareholder attributable to such partner.

CLIENTS

     We ended 2000 with 2,315 client contracts. Our client base is a diverse
group of large and small companies in the Internet, media, telecommunications,
technology, financial services, consumer products, retail, travel and
professional services industries. Clients who subscribe for our measurement
services typically use our data for planning, buying and selling advertising;
developing e-commerce strategies; understanding consumer behavior; gaining
competitive market intelligence; and analyzing investment decisions. The users
of our research products and services at our client companies hold diverse
positions, demonstrating the importance of Internet commerce to a company's
overall strategy and development. In addition to chief executive officers and
presidents, our users include marketing, business development, operations,
strategic planning and information technology executives.

     We typically enter into 12-month or longer subscription contracts with our
clients, some of whom are covered by multi-client master contracts with parent
corporations, to provide standard, syndicated products and services or
customized reports and analyses. It is typical for our clients to initially
purchase one of our standard products and to upgrade over time. No client
accounted for more than 2% of our revenues in 2000.

SALES AND MARKETING

     We sell and market our products through our direct sales force, which was
comprised of 168 sales representatives as of March 15, 2001. Our U.S. sales
force operates from our New York, San Francisco Bay Area and Seattle offices,
and we maintain local representatives in various locations throughout the United
States. We also maintain international sales offices in Buenos Aires, London,
Madrid, Milan, Nurnberg, Paris, Sao Paolo, Tokyo, Toronto, Stockholm and Zurich.
Sales representatives receive a base salary and are eligible for commissions
based on sales and revenue goals. We support our sales efforts through marketing
and brand building activities. We use public relations, user group seminars,
trade shows and speaking engagements to create publicity.

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OPERATIONS AND TECHNOLOGY

     We have built our primary data collection, retrieval and processing system
based on systems and software developed by The NPD Group, Inc. Our system has
been designed around industry standard data architectures. Backup procedures are
built into the processing environment in order to reduce downtime in the event
of outages or catastrophic occurrences. Our hardware systems are hosted at our
Uniondale, New York facility, which will be moved to our new facility in
Melville, New York during the second quarter of 2001, our Seattle, Washington
facility, and at three offsite professionally-managed computer centers in New
York, New York and Santa Clara, California.

     As of March 15, 2001, we had 99 employees dedicated to research and
development. We incurred research and development expenses of $1.4 million in
1998, $5.0 million in 1999 and $16.1 million in 2000. At the end of the second
quarter of 2001, we plan to fully implement our new data warehouse. Our client
interface systems were introduced in the first half of 2000, resulting in
increases in research and development personnel and consulting costs. We
anticipate that we will continue to devote significant resources to product
development and the development of delivery technology in the future as we add
new reports and databases.

INTELLECTUAL PROPERTY

     We regard the protection of our patents, copyrights, service marks,
trademarks and trade secrets as important to our future success and rely on a
combination of patent, copyright, trademark, service mark and trade secret laws
and contractual restrictions to establish and protect our proprietary rights. We
require employees and contractors to enter into confidentiality and invention
assignment agreements, and we enter into nondisclosure agreements with third
parties with whom we do business in order to limit access to and disclosure of
our proprietary information. We cannot assure you that these contractual
arrangements or the other steps we have taken or will take in the future will be
sufficient to protect our technology from infringement or misappropriation or to
deter independent development of similar or superior technologies by others.

     We seek to obtain the issuance of patents and the registration of our
trademarks and service marks in the United States and in selected other
countries. Effective patent, trademark, service mark, copyright and trade secret
protection may not be available in every country in which our products and
services are or will be made available to the same extent such protection is
available in the United States. We also expect to license proprietary rights
such as patents, trademarks or copyrighted material to strategic partners in the
course of our international expansion. While we will attempt to ensure that the
quality of our service is maintained by such licensees, we cannot assure you
that such licensees will not take actions that might materially adversely affect
the value of our proprietary rights or reputation, which could have a material
adverse effect on our business, results of operations and financial condition.

     We have been issued two patents in the United States with regard to our
meter methodology (U.S. Patent No. 5,675,510 and U.S. Patent No. 6,115,680).
Patents covering the technology covered by U.S. Patent No. 5,675,510 have also
been issued in Australia and Norway. We also have patent applications pending in
the European Patent office and in Brazil, Canada, Japan, Mexico and the United
States.

     We have also applied for a patent in the United States and other foreign
jurisdictions on the methodology for monitoring of remote data access on a
public computer network which comprises the former RelevantKnowledge meter. This
application was rejected by the U.S. Patent and Trademark Office in June 2000.
We are currently challenging this rejection and intend to revive our
application.

     In September 2000, we filed a complaint for patent infringement against PC
Data, Inc. Our complaint sought money damages from and a permanent injunction
against PC Data. In October 2000, PC Data filed its answer, defenses and
counterclaims to our complaint seeking declaratory judgments of noninfringement
and invalidity. In March 2001, the parties reached a settlement of the
litigation. As part of the settlement, PC Data (1) has consented to a finding
that our U.S. Patent No. 6,115,680 is valid and enforceable; (2) has consented
to a finding that it has infringed our patent; (3) has consented to a permanent
injunction enjoining it from continuing to infringe our patent; and (4) has
transferred its rights to the systems and methods used to

                                        8
<PAGE>

monitor computer and online activity, including its @PC Data Tracking Software
and related technologies, to us.

     On March 27, 2001, we filed a complaint for patent infringement against
NetRatings, Inc. and NetValue USA, Inc. in federal district court in the
District of Delaware. Our complaint seeks money damages from and a permanent
injunction against both NetRatings and NetValue.

     Our use of the brand name "Media Metrix" in Europe had been challenged by
Mediametrie, S.A., a French company which measures audiences of various media.
Rather than engage in a protracted dispute, we elected to have our European
joint venture conduct business under the name "MMXI Europe." Mediametrie had
also challenged our use of the domain name "mediametrix.com."

     Our failure to adequately protect our intellectual property, either in the
United States or abroad, could harm the Jupiter Media Metrix brand or our
trademarks, devalue our proprietary data, research and analysis and affect our
ability to compete effectively. Defending our intellectual property rights could
result in the expenditure of significant financial and managerial resources,
which could have a material adverse effect upon our business, results of
operations and financial condition.

     To date, we have not been notified that our technologies infringe the
proprietary rights of third parties. We cannot assure you that others will not
claim that we have misappropriated a trade secret or infringed a patent,
copyright, trademark or other proprietary right belonging to them with respect
to past, current or future technologies. We expect that the number of
infringement claims in our market will increase as the number of services and
competitors in our industry grows. Any of those claims, whether meritorious or
not, could be time-consuming, result in costly litigation, may distract
management from other tasks of operating the business and may result in the loss
of significant rights or require us to enter into royalty or licensing
agreements. Royalty or licensing agreements might not be available on terms we
find acceptable or at all. As a result, any such claim could have a material
adverse effect upon our business, results of operations and financial condition.

COMPETITION

     We believe that the primary competitive factors determining success in our
markets include:

     - the accuracy and timeliness of global measurement services of proprietary
       online services and Internet-related activity, as well as measuring Web
       activity, that are based on a consistent standard methodology;

     - the quality and timeliness of our research, analysis and conferences;

     - the accuracy of the measurement of advertising on the Internet and other
       digital media;

     - the creation of high-quality, timely and reliable consumer and business
       panels of a sufficient size and representative nature to provide the
       necessary data;

     - our ability to offer products and services that meet the changing needs
       of our customers;

     - the prices we charge for our various measurement and research products
       and general economic conditions; and

     - the establishment of credibility as a trusted independent source of data.

     We believe that we compete favorably with respect to each of these factors.
In addition, we believe that we distinguish ourselves from our competitors as a
result of the timeliness and quality of our Internet measurement services and
methodology, the depth and breadth of our research services, including the
extent to which we provide access to our research analysts, the quality of our
research analysts and sales representatives, the relevance of our conference
topics and the primary measurement and research tools and proprietary databases
that we have developed internally.

     In March 1999, NetRatings and Nielsen Media Research introduced a new Web
site ratings service, Nielsen//NetRatings, which competes directly with many
aspects of our audience measurement services.
                                        9
<PAGE>

Nielsen Media Research is the leading provider of television audience
measurement services in the United States and Canada. In September 1999,
NetRatings also entered into a joint venture with ACNielsen Corp. to develop and
maintain audience measurement panels and to market Nielsen//NetRatings' products
and services in international markets. ACNielsen is a leading provider of market
research, information and analysis to consumer products and services industries
and is a provider of television audience measurement services outside the United
States and Canada. In December 1999, Nielsen Media Research became a majority
shareholder of NetRatings. Subsequently, VNU B.V., a leading media and
information company, purchased both AC Nielsen and Nielsen Media Research.
Nielsen Media Research, ACNielsen and VNU have significantly more financial and
other resources than do we. In light of these events, Nielsen//NetRatings has
become a significant competitor to our measurement business. We also face
competition from NetValue, a French company which has begun providing audience
measurement services in Europe and the United States.

     We also compete indirectly with operators of site-centric and other
consumer-centric measurement systems. Site-centric measurement systems measure
audience visits at a specific Web site by monitoring the Web site's server.
Consumer-centric systems measure the market either in a manner similar to us or
qualitatively through on-line and telephonic interviews. Lastly, we may face
increased competition from individual Web sites that develop an independent
method of measuring their own audience and from other companies that develop
alternative audience measurement technologies to those already provided by us or
our current competitors. In March 2001, DoubleClick Inc. and comScore Networks
announced a joint marketing plan for a new online audience measurement product,
NetScore which uses data gathered from comScore's large database of traffic
information from its opt-in users. NetScore uses a methodology different than
both our measurement model and the site-centric models. We may face
significantly increased competition from this new service if NetScore is able to
take advantage of the significant financial and marketing resources of
DoubleClick and comScore or if NetScore's methodology becomes generally
accepted.

     In the market for Internet commerce-related research products and services,
our principal competitor is Forrester Research, Inc. Numerous other companies
compete with us both domestically and internationally in providing research and
analysis related to a specific industry or geographic area. In addition, we face
increased direct and indirect competition from information technology research
firms, business consulting and accounting firms, electronic and print publishing
companies and equity analysts employed by financial services companies. We also
face strong competition in the business of producing conferences related to
Internet commerce, and an increasing number of companies are sponsoring these
conferences in the United States and abroad. These competitors include
publishing and media companies, research providers, financial services companies
and consulting firms and companies which focus solely on the production of
conferences.

     We expect competition to increase because of the business opportunities
presented by the growth of Internet commerce around the world. Competition may
also intensify as a result of industry consolidation, because of technological
advancements in the way to measure Internet activity or because some of our
competitors may be able to provide additional or complementary services, such as
consulting services. Increased competition may result in reduced operating
margins, loss of market share and diminished value in our services, as well as
different pricing, service or marketing decisions.

EMPLOYEES

     As of February 28, 2001, we had 882 full-time employees worldwide. None of
our employees is covered by a collective bargaining agreement. We have never
experienced an employment-related work stoppage and consider our employee
relations to be good.

                                        10
<PAGE>

ITEM 2.  PROPERTIES

     Currently, we lease office space in New York, New York, Atlanta, Georgia,
San Francisco, California, Los Altos, California, Berkeley, California, Seattle,
Washington, Toronto, Canada, London, England, Tokyo, Japan, Stockholm, Sweden
and Sydney, Australia. In addition, our operations and research and development
facility is currently located in Uniondale, New York, which is leased to us by
The NPD Group, Inc. under the terms of a management services agreement. We will
be transferring our operations and research and development facility to a new
leased location in Melville, NY. We anticipate completing such transfer during
the second quarter of 2001.

ITEM 3.  LEGAL PROCEEDINGS

     On September 28, 2000, we filed a complaint for patent infringement against
PC Data, Inc. in Federal District Court in the District of Delaware, Jupiter
Media Metrix, Inc. v. PC Data, Inc., Civil Action No. 00-874-SLR. Our complaint
sought money damages from and a permanent injunction against PC Data. On October
18, 2000, PC Data filed its answer, defenses and counterclaims to our complaint.
PC Data's Counterclaims sought declaratory judgments of noninfringment and
invalidity. In March 2001, the parties reached a settlement of the litigation.
As part of the settlement, PC Data (1) has consented to a finding that our U.S.
Patent No. 6,115,680 is valid and enforceable; (2) has consented to a finding
that it has infringed the '680 patent; (3) has consented to a permanent
injunction enjoining it from continuing to infringe the '680 patent; and (4) has
transferred its rights to the systems and methods used to monitor computer and
online activity, including its @PC Data Tracking Software and related
technologies, to us.

     On March 27, 2001, we filed a complaint for patent infringement against
NetRatings, Inc. and NetValue USA, Inc. in federal district court in the
District of Delaware. Our complaint seeks money damages from and a permanent
injunction against both NetRatings and NetValue.

ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

     No matters were submitted to a vote of security holders in the fourth
quarter of 2000.

                                     PART I

ITEM 5.  MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER MATTERS.

     Our common stock has been listed on the NASDAQ National Market since May 7,
1999, the date of our initial public offering. We traded under the symbol "MMXI"
from May 7, 1999 to September 20, 2000, the date of our merger with Jupiter
Communications, Inc. and under the symbol "JMXI" since September 20, 2000. The
following table sets forth the high and low closing sale prices on the NASDAQ
National Market for our common stock for the calendar periods indicated.

<Table>
<Caption>
                                                              PRICE RANGE
                                                            OF COMMON STOCK
                                                           ------------------
                                                            HIGH        LOW
                                                           -------    -------
<S>                                                        <C>        <C>
YEAR ENDED DECEMBER 31, 2000:
First Quarter............................................  $47.875    $28.000
Second Quarter...........................................  $45.250    $20.438
Third Quarter............................................  $29.188    $14.750
Fourth Quarter...........................................  $16.125    $ 6.000

YEAR ENDED DECEMBER 31, 1999:
Second Quarter...........................................  $56.625    $32.000
Third Quarter............................................  $69.875    $34.250
Fourth Quarter...........................................  $65.875    $32.500
</Table>

     As of March 15, 2001, there were 668 holders of record of our common stock.

                                        11
<PAGE>

DIVIDEND POLICY

     We have never declared nor paid any cash dividends on our common stock. We
currently anticipate that we will retain any future earnings for the development
and operations of our business. Accordingly, we do not anticipate paying cash
dividends on our capital stock in the foreseeable future.

CHANGES IN SECURITIES AND USE OF PROCEEDS

     The effective date of our first registration statement, filed on Form S-1
under the Securities Act of 1933 (No. 333-72883) relating to the initial public
offering of our common stock, was May 6, 1999. A total of 3,250,000 shares of
our common stock were sold at a price of $17.00 per share to an underwriting
syndicate led by Donaldson, Lufkin & Jenrette Securities Corporation, BancBoston
Robertson Stephens Inc. and Thomas Weisel Partners LLC. The offering commenced
on May 7, 1999, and closed on May 12, 1999. An additional 200,000 shares of
common stock were sold on behalf of selling stockholders as part of the same
offering. The initial public offering resulted in gross proceeds to us of $55.3
million, $3.9 million of which was applied toward the underwriting discount.
Expenses related to the offering totaled approximately $2.0 million. Net
proceeds to us and the selling stockholders were $49.4 million and $3.2 million,
respectively. From the time of receipt through December 31, 2000, proceeds were
applied as follows:

     - $4.8 million towards the redemption of our redeemable preferred stock
       from The NPD Group, Inc.;

     - $5.7 million for the Internet audience measurement business operated by
       SIFO Group AB in Sweden; and

     - the remaining $38.9 million was used for working capital purposes.

     From October 1, 1999 through December 31, 1999, we issued 697,664 shares of
our common stock to the shareholders of AdRelevance in connection with our
acquisition of AdRelevance in October 1999. On October 8, 2000, we issued an
additional 82,921 shares of common stock and 17,450 options based upon
AdRelevance's achievement of certain post-closing goals in connection with the
acquisition of AdRelevance.

     No underwriters were engaged in connection with the issuance of the shares
to the AdRelevance shareholders. The issuance of the shares was made in reliance
upon the exemption from registration set forth in Section 4(2) of the Securities
Act of 1933.

     In October 1999, we consummated a secondary offering of 3,000,000 shares of
common stock at a price of $50.50 per share. Of the 3,000,000 shares sold,
1,500,000 shares were sold by us and 1,500,000 shares were sold by existing
stockholders. Net proceeds to us were $71,095,000 after deducting the
underwriters' discount and related expenses.

     In September 2000, we completed our merger with Jupiter Communications by
issuing 14,921,856 shares of our common stock in exchange for all of the
outstanding common stock of Jupiter Communications. In addition, we assumed all
of the outstanding stock options to purchase common stock of Jupiter
Communications. The total purchase price was $470.1 million, including
merger-related expenses of approximately $6.9 million.

                                        12
<PAGE>

ITEM 6.  SELECTED CONSOLIDATED FINANCIAL DATA.

     The financial data set forth below should be read in conjunction with
"Management's Discussion and Analysis of Financial Condition and Results of
Operations" and with the Company's Consolidated Financial Statements and notes
thereto included elsewhere in this Form 10-K. The financial statements for the
year ended December 31, 2000 include the operations of Jupiter Communications,
Inc. from September 21, 2000, the date of our merger. The financial statements
for the year ended December 31, 1996 are those of PC Meter, our predecessor, and
include three months of operations during which PC Meter was still a division of
The NPD Group, Inc.

<Table>
<Caption>
                                                        YEAR ENDED DECEMBER 31,
                                         -----------------------------------------------------
                                           2000        1999       1998       1997       1996
                                         --------    --------    -------    -------    -------
                                                 (IN THOUSANDS, EXCEPT PER SHARE DATA)
<S>                                      <C>         <C>         <C>        <C>        <C>
STATEMENT OF OPERATIONS DATA:
Revenues:
  Measurement..........................  $ 51,829    $ 20,500    $ 6,331    $ 3,188    $ 1,033
  Research services....................    17,238          --         --         --         --
  Events and other.....................     8,711          --         --         --         --
                                         --------    --------    -------    -------    -------
Total revenues.........................    77,778      20,500      6,331      3,188      1,033
Cost of revenues.......................    32,752      10,291      4,121      3,463      1,744
                                         --------    --------    -------    -------    -------
Gross profit (loss)....................    45,026      10,209      2,210       (275)      (711)
Operating expenses:
  Research and development.............    16,078       5,044      1,382        866        588
  Sales and marketing..................    29,428       9,117      2,888      2,022        929
  General and administrative...........    25,882       6,756      2,715      1,516      1,148
  Amortization of deferred compensation
     and other stock-based
     compensation......................     2,551       1,060        369         --         --
  Amortization of intangibles..........    46,629       7,312        479         --         --
  Acquired in-process research and
     development.......................        --       6,800      1,600         --         --
                                         --------    --------    -------    -------    -------
Total operating expenses...............   120,568      36,089      9,433      4,404      2,665
                                         --------    --------    -------    -------    -------
Loss from operations...................   (75,542)    (25,880)    (7,223)    (4,679)    (3,376)
Minority interests.....................     5,990       1,689         --         --         --
Interest and other income, net.........     6,231       2,283         65         95         --
                                         --------    --------    -------    -------    -------
Net loss...............................   (63,321)    (21,908)    (7,158)    (4,584)    (3,376)
Preferred stock dividends..............        --        (109)      (314)      (290)        --
                                         --------    --------    -------    -------    -------
Net loss applicable to common
  stockholders.........................  $(63,321)   $(22,017)   $(7,472)   $(4,874)   $(3,376)
                                         ========    ========    =======    =======    =======
Basic and diluted net loss per common
  share applicable to common
  stockholders.........................  $  (2.63)   $  (1.34)   $  (.98)   $  (.75)   $  (.52)
                                         ========    ========    =======    =======    =======
Shares used in the calculation of basic
  and diluted net loss per share
  applicable to common stockholders....    24,083      16,445      7,619      6,523      6,523
</Table>

                                        13
<PAGE>

<Table>
<Caption>
                                                            AT DECEMBER 31,
                                         -----------------------------------------------------
                                           2000        1999       1998       1997       1996
                                         --------    --------    -------    -------    -------
                                                            (IN THOUSANDS)
<S>                                      <C>         <C>         <C>        <C>        <C>
BALANCE SHEET DATA
  Cash, cash equivalents and marketable
     securities........................  $ 92,213    $112,241    $ 8,012    $ 1,869    $   583
  Working capital (deficit)............    57,559     102,806      1,057        (47)    (2,478)
  Total assets.........................   646,976     178,844     16,060      2,787      1,213
  Due to related parties...............     3,646         444      4,706      1,284      2,782
  Preferred stock......................        --          --      4,680      8,366         --
  Total stockholders' equity
     (deficit).........................   568,824     162,789      2,622     (8,274)    (2,478)
</Table>

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS

     You should read the following discussion of our financial condition and
results of operations with the financial statements and the notes to the
financial statements included elsewhere in this Annual Report on Form 10-K. This
discussion contains forward-looking statements, within the meaning of the
Private Securities Litigation Reform Act of 1995, based on our current
expectations, assumptions, estimates and projections. These forward-looking
statements involve risks and uncertainties. Our actual results could differ
materially from those anticipated in these forward-looking statements as a
result of certain factors, as more fully described in the "Risk Factors" section
and elsewhere in this Annual Report on Form 10-K. We undertake no obligation to
update publicly any forward-looking statements for any reason, even if new
information becomes available or other events occur in the future.

OVERVIEW

     Jupiter Media Metrix, Inc. is a global provider of innovative and
comprehensive research and measurement products and services that analyze the
impact of the Internet and new technologies on commerce and marketing. Our
business units include Media Metrix, Jupiter Research, AdRelevance and Jupiter
Events. Media Metrix offers clients a broad range of products and services that
collect audience data and measure new media usage on the Internet and other
digital media. Jupiter Research provides business-to-business and
business-to-consumer clients with strategic analysis and insights, including
industry trends, forecasts and best practices, all backed by proprietary data.
AdRelelvance specializes in the automated retrieval and delivery of online
advertising data. Jupiter Events hosts conferences focusing on the global
digital economy.

     Our business was originally conducted as a division within The NPD Group,
Inc. ("NPD"), a leading marketing research firm. Prior to March 1996, we were
engaged primarily in product research and development. In March 1996, PC Meter,
L.P., was formed to further commercialize our Internet audience measurement
business in an entity separate from NPD. In April 1997, PC Meter was merged into
Media Metrix, Inc. and we raised approximately $4.0 million in a private
placement to fund the expansion of our Internet audience measurement business.

     In November 1998, we merged with RelevantKnowledge, then our leading
competitor for Internet audience measurement services. In October 1999, we
acquired AdRelevance in a stock-for-stock transaction valued at approximately
$59.4 million. In connection with our acquisition of AdRelevance, we recognized
$54.3 million of intangibles, which are being amortized over a three-year
period. In addition, in October 2000, we issued an additional 82,921 shares of
our common stock and 17,450 options, based on the achievement of certain
post-closing milestones, in connection with the acquisition of AdRelevance,
which resulted in goodwill of approximately $995,000.

     On September 20, 2000, we completed our merger with Jupiter Communications,
Inc. ("Jupiter Communications") for a total purchase price of $470.1 million,
including merger-related expenses of approximately $6.9 million. In connection
with this transaction, we recognized $14.6 million in deferred compensation,
which represents the intrinsic value of unvested options to purchase common
stock of Jupiter Communications, which will be amortized over the remaining
vesting period of the options. We recorded

                                        14
<PAGE>

goodwill and other intangibles of $391.6 million, which will be amortized over a
five-year period. The operations of Jupiter Communications from September 21,
2000 have been included in the financial statements and financial information
included in this annual report.

     We have entered into a number of joint venture and licensing agreements to
offer our products and services in foreign countries. In connection with the
formation of the international joint ventures, we have granted each of our joint
venture partners an option, subject to certain conditions, to exchange such
partner's shares in the respective joint ventures for shares of our common
stock. If any partner elects to exercise its option to convert its shares into
shares of our common stock, we will need to record additional goodwill in an
amount equal to the difference between the then fair market value of our shares
of common stock multiplied by the number of shares issued and the net book value
of the joint venture of which the partner is a shareholder attributable to such
partner. The minority interests related to each joint venture, included in our
statement of operations, consist of the loss related to our partners' interests
in our foreign subsidiaries.

     Our revenues consist of measurement products and services, research
services and events and other revenues. Prior to our merger with Jupiter
Communications, our revenues were derived solely from our measurement products
and services.

     Our measurement offerings, which consist of the products and services from
our Media Metrix and AdRelevance units, include both syndicated measurement
products and customized measurement products. We sell our syndicated measurement
products on an annual subscription basis, and typically bill our syndicated
clients, in advance, for up to the next twelve months of products. Contracts for
our syndicated measurement products are generally non-cancelable and
non-refundable. For the past three years, syndicated measurement products
accounted for approximately 90% of our measurement revenues, while customized
measurement products and services accounted for approximately 10%. We recognize
revenues for the syndicated measurement products and services over the term of
the related contract as services are provided. Revenues for customized
measurement products and services are recognized in the period in which the
product or service is delivered.

     Our research offerings, which consist of the products and services from our
Jupiter Research unit, are a combination of proprietary written analysis,
supporting data and access to our research analysts. As with our syndicated
measurement products, we typically sell our Jupiter Research products on an
annual subscription basis and bill the clients in advance. Jupiter Research
contracts are generally non-cancelable and non-refundable. We recognize revenues
for our Jupiter Research products and services over the term of the related
contract as services are provided. For the year ended December 31, 2000,
syndicated research products accounted for 92.7% of our research revenues, while
7.3% was from the sale of book-length studies and custom research products.
Revenues from these services are recognized upon the sale of the study or
completion of the project. We also produce, through our Jupiter Events unit, a
wide range of conferences and forums which offer senior executives the
opportunity to hear first-hand the insights of our research analysts and the
leading decision makers in the Internet and technology industries. Our Jupiter
Events revenues consist of revenues from (i) individual attendees, (ii)
sponsors, which display their logo in our conference program and/or host a
reception, and (iii) exhibitors, which receive a booth to promote their
companies. Other revenues are derived primarily from the sale of Web
sponsorships. Revenues attributable to our conferences and other services are
recognized upon the completion of the event and over the term of the Web
sponsorship.

     Our growing client base, which totaled over 2,300 client contracts at the
end of 2000, is highly diversified and includes companies in the advertising,
financial services, technology and Internet, media, telecommunications, retail,
travel, consumer products and professional service industries.

     We have incurred significant losses from operations since our inception. We
incurred losses from operations of $75.5 million in the fiscal year ended
December 31, 2000, $25.9 million in 1999 and $7.2 million in 1998. As of
December 31, 2000, we had an accumulated deficit of $101.4 million. We expect
that we will incur significant expenses in the future associated with our
ongoing international expansion, particularly costs associated with recruiting
and maintaining panels in a number of countries, investing in further developing
and improving of our technologies and developing additional products and
services.

                                        15
<PAGE>

RESULTS OF OPERATIONS

     The following table sets forth our results of operations expressed as a
percentage of revenues:

<Table>
<Caption>
                                                             YEAR ENDED DECEMBER 31,
                                                            -------------------------
                                                            2000      1999      1998
                                                            -----    ------    ------
<S>                                                         <C>      <C>       <C>
Revenues:
  Measurement.............................................   66.6%    100.0%    100.0%
  Research services.......................................   22.2        --        --
  Events and other........................................   11.2        --        --
                                                            -----    ------    ------
Total revenues............................................  100.0     100.0     100.0
Cost of revenues..........................................   42.1      50.2      65.1
                                                            -----    ------    ------
Gross profit..............................................   57.9      49.8      34.9
Operating expenses:
  Research and development................................   20.7      24.6      21.8
  Sales and marketing.....................................   37.8      44.5      45.6
  General and administrative..............................   33.3      33.0      42.9
  Amortization of deferred compensation and other
     stock-based compensation.............................    3.2       5.1       5.8
  Amortization of intangibles.............................   60.0      35.7       7.6
  Acquired in-process research and development............     --      33.1        --
                                                            -----    ------    ------
Total operating expenses..................................  155.0     176.0     149.0
                                                            -----    ------    ------
Loss from operations......................................  (97.1)   (126.2)   (114.1)
Minority interests........................................    7.7       8.2        --
Interest and other income, net............................    8.0      11.1       1.0
                                                            -----    ------    ------
Net loss..................................................  (81.4)%  (106.9)%  (113.1)%
                                                            =====    ======    ======
</Table>

  Year Ended December 31, 2000 Compared to Year Ended December 31, 1999

     Revenues.  Revenues increased 279.4% to $77.8 million for the year ended
December 31, 2000 from $20.5 million for the year ended December 31, 1999. Of
that increase, $25.9 million relates to revenues from Jupiter Communications for
the period following the closing of the merger on September 20, 2000. Of the
$25.9 million, $15.3 million can be attributed to Jupiter research services and
the balance of $10.6 million to events and other revenues. Sales of syndicated
measurement products and services accounted for approximately 96% of measurement
revenues for the year ended December 31, 2000 as compared to 90% for the year
ended December 31, 1999. Sales of customized measurement products and services
accounted for the remaining measurement revenues in the year ended December 31,
2000. Sales of syndicated research products and services accounted for
approximately 92.7% of research revenues for the year ended December 31, 2000.
Sales from our events and customized research products and services accounted
for the remaining research revenues in the year ended December 31, 2000. In
addition to revenues attributable to Jupiter Communications, the increase in
revenues was due primarily to a substantial increase in the number of customers,
including new customers as a result of international growth, and an increase in
the amount of products and services sold to our customers.

     Cost of Revenues.  Cost of revenues consists primarily of costs associated
with the recruitment and maintenance of our panels, data collection, costs
associated with our research analysts, event costs and production costs. Panel
and data collection costs include costs associated with mailing and printing,
incentives, help desk and associated personnel. Production costs include
computer usage charges, printing, report distribution costs and personnel costs.
Gross profit was $45.0 million for the year ended December 31, 2000, or 57.9% of
revenues. Gross profit was $10.2 million for the year ended December 31, 1999,
or 49.8% of revenues. The increase in gross profit as a percentage of revenues
for the year ended December 31, 2000 over the prior

                                        16
<PAGE>

period was due to an increase in revenues partially offset by costs related to
recruiting panels and other start-up costs in connection with our international
operations. Jupiter Communications contributed $14.1 million in gross profit for
the period following the closing of the merger.

     Research and Development.  Research and development costs consist primarily
of personnel and other related costs attributable to the development of new
products and services. All research and development costs have been expensed as
incurred. Research and development costs were $16.1 million for the year ended
December 31, 2000, or 20.7% of revenues. Research and development costs were
$5.0 million for the year ended December 31, 1999, or 24.6% of revenues. The
increase in research and development costs in absolute dollars for the year
ended December 31, 2000 was due primarily to increases in research and
development personnel and consulting costs, including certain costs relating to
our new meter and client interface systems which were introduced in the second
quarter of 2000.

     Sales and Marketing.  Sales and marketing costs consist of salaries,
bonuses, commissions, travel and expenses, promotional costs, and other costs
incurred in marketing and selling our products and services. Sales and marketing
costs were $29.4 million for the year ended December 31, 2000, or 37.8% of
revenues. Sales and marketing costs were $9.1 million for the year ended
December 31, 1999, or 44.5% of revenues. The increase in absolute dollars was
due primarily to the increase in sales and marketing personnel, both in the
United States and abroad, as well as additional marketing costs. The inclusion
of Jupiter Communications for the period following the merger resulted in an
additional $7.3 million in sales and marketing costs.

     General and Administrative.  General and administrative costs consist
primarily of personnel, lease payments for our facilities, telephone and
utilities and professional services fees. General and administrative costs were
$25.9 million for the year ended December 31, 2000, or 33.3% of revenues.
General and administrative costs were $6.8 million for the year ended December
31, 1999, or 33.0% of revenues. The increase in absolute dollars was due to the
expenses associated with our international expansion and increased personnel and
expansion of our office facilities. The inclusion of Jupiter Communications for
the period following the merger resulted in an additional $9.3 million in
general and administrative costs.

     Amortization of Deferred Compensation and Other Stock-based
Compensation.  Amortization of deferred compensation and other stock-based
compensation of $2.5 million for the year ended December 31, 2000 includes $1.6
million related to the amortization of deferred compensation recorded in
connection with our merger with Jupiter Communications. The remaining $900,000
for the year ended December 31, 2000 and $1.1 million for the year ended
December 31, 1999 represents a non-cash compensation expense recorded in
connection with stock options granted in 2000, 1999 and 1998, and the
acceleration of the vesting provisions of certain stock options resulting in a
new measurement date.

     Amortization of Intangibles.  Amortization charges of $46.6 million for the
year ended December 31, 2000 represent the amortization of intangibles acquired
in our mergers with Jupiter Communications of $24.2 million and
RelevantKnowledge of $1.8 million, and our acquisitions of AdRelevance of $18.2
million and MMXI Nordic of $2.4 million. Amortization charges of $7.3 million
for the year ended December 31, 1999 represent the amortization of
RelevantKnowledge's panel and amortization of other intangibles acquired in our
merger with RelevantKnowledge, as well as amortization of intangibles acquired
in our acquisition of AdRelevance.

     Acquired In-Process Research and Development.  In connection with the
acquisition of AdRelevance, we expensed $6.8 million of acquired in-process
research and development for the year ended December 31, 1999. Acquired
in-process research and development represents the value attributed to the
technologies in development at the time of the acquisition.

     Loss from Operations.  Loss from operations was $75.5 million for the year
ended December 31, 2000, or 97.1% of revenues. Our loss from operations was
$25.9 million for the year ended December 31, 1999, or 126.2% of revenues. Loss
from operations in terms of absolute dollars was higher in the year ended
December 31, 2000 due to the continued expansion of our business in the United
States and internationally and the amortization of intangibles. The increase in
loss from operations as a percentage of revenues was due to an increase in
amortization of intangibles from the AdRelevance and MMXI Nordic acquisitions
and our

                                        17
<PAGE>

merger with Jupiter Communications, offset by an increase in revenues relative
to increases in costs of revenue and operating costs. We expect these losses to
continue as our business continues to expand both in the United States and
internationally.

     Minority Interests.  Minority interests increased from $1.7 million for the
year ended December 31, 1999 to $6.0 million for the year ended December 31,
2000 because of expansion of international operations in which we have partners
with minority interests. Minority interests consist of the loss related to our
partners' interests in our foreign subsidiaries.

     Interest and Other Income, net.  Interest and other income, net of interest
expense, was $6.2 million, or 8.0% of revenues, for the year ended December 31,
2000 as compared to $2.3 million, or 11.1% of revenues, for the year ended
December 31, 1999. The increase in interest and other income was due to the
investment of the proceeds of our initial and secondary public offerings, as
well as cash and cash equivalents acquired in the Jupiter Communications merger.

  Year Ended December 31, 1999 Compared to Year Ended December 31, 1998

     Revenues.  Revenues increased 223.8% to $20.5 million for the year ended
December 31, 1999 from $6.3 million for the year ended December 31, 1998. Sales
of syndicated audience measurement products and services accounted for
approximately 90% of revenues for each of the years ended December 31, 1999 and
1998. Sales of customized products and services accounted for the remaining
revenues. The increase in revenues was due primarily to a substantial increase
in the number of customers, including customers acquired in connection with the
RelevantKnowledge merger, and an increase in the amount of products and services
sold to customers.

     Costs of Revenues.  Gross profit was $10.2 million for the year ended
December 31, 1999, or 49.8% of revenues. Gross profit was $2.2 million for the
year ended December 31, 1998, or 34.9% of revenues. The increase in gross profit
as a percentage of revenues for the year ended December 31, 1999 over the prior
period was due to an increase in revenues, without a commensurate increase in
costs.

     In the year ended December 31, 1999, we invested approximately $2.5 million
in recruiting panels and other start up costs in connection with our
international operations in the U.K., France, Germany, Canada and Australia.
However, we did not realize any significant revenues to offset against these
costs, which resulted in a lower overall gross margin for the period compared to
the gross margin applicable to the U.S. operations alone for the same period.

     Research and Development.  Research and development costs were $5.0 million
for the year ended December 31, 1999, or 24.6% of revenues. Research and
development costs were $1.4 million for the year ended December 31, 1998, or
21.8% of revenues. The increase in research and development costs as a
percentage of revenues for the year ended December 31, 1999 was due primarily to
increases in research and development personnel and consulting costs, including
certain costs relating to our new meter, data warehouse and client interface
systems.

     Sales and Marketing.  Sales and marketing costs were $9.1 million for the
year ended December 31, 1999, or 44.5% of revenues. Sales and marketing costs
were $2.9 million for the year ended December 31, 1998, or 45.6% of revenues.
The increase in absolute dollars was due primarily to the increase in sales and
marketing personnel, including the addition of personnel in connection with the
RelevantKnowledge merger, our acquisition of AdRelevance and our international
expansion, as well as additional marketing costs. The decrease in sales and
marketing costs as a percentage of revenues was due primarily to revenues
increasing at a greater rate.

     General and Administrative.  General and administrative costs were $6.8
million for the year ended December 31, 1999, or 33.0% of revenues. General and
administrative costs were $2.7 million for the year ended December 31, 1998, or
42.9% of revenues. The increase in absolute dollars was due to the expenses
associated with becoming a public company, our international expansion and
increased personnel and expansion of our office facilities, including the
addition of personnel and office facilities in connection with the

                                        18
<PAGE>

RelevantKnowledge merger and our acquisition of AdRelevance. The decrease in
general and administrative costs as a percentage of revenues was due primarily
to revenues increasing at a greater rate.

     Amortization of Deferred Compensation and Other Stock-based
Compensation.  Amortization of deferred compensation and other stock-based
compensation of $1.1 million for the year ended December 31, 1999 and $369,000
for the year ended December 31, 1998 represents a non-cash compensation expense
recorded in connection with stock options granted in 1999 and 1998 and the
acceleration of the vesting provisions of certain stock options resulting in a
new measurement date in 1999.

     Amortization of Intangibles.  Amortization charges of $7.3 million for the
year ended December 31, 1999 represent the amortization of RelevantKnowledge's
panel and amortization of other intangibles acquired in our merger with
RelevantKnowledge, as well as amortization of intangibles acquired in our
acquisition of AdRelevance. Amortization charges of $479,000 for the year ended
December 31, 1998 represent the amortization of RelevantKnowledge's panel and
other intangibles acquired in the merger.

     Acquired In-Process Research and Development.  In connection with the
acquisition of AdRelevance, we expensed $6.8 million of acquired in-process
research and development for the year ended December 31, 1999. In connection
with the acquisition of RelevantKnowledge, we expensed $1.6 million for the year
ended December 31, 1998.

     Loss from Operations.  Our loss from operations was $25.9 million for the
year ended December 31, 1999, or 126.2% of revenues. Loss from operations was
$7.2 million for the year ended December 31, 1998, or 114.1% of revenues. Loss
from operations in terms of absolute dollars was higher in the year ended
December 31, 1999 due to the continued expansion of our business in the United
States and internationally, the merger with RelevantKnowledge, the acquisition
of AdRelevance and amortization of intangibles. The increase in loss from
operations as a percentage of revenues was due to a full year of amortization of
intangibles from the RelevantKnowledge merger and the write-off of acquired
in-process research and development from the AdRelevance acquisition for the
year ended December 31, 1999 offset by an increase in revenues relative to the
increases in costs of revenues and operating costs.

     Interest and Other Income, net.  Interest and other income, net of interest
expense was $2.3 million, or 11.1% of revenues, for the year ended December 31,
1999 as compared to $65,000 for the year ended December 31, 1998, or 1.0% of
revenues. The increase in interest and other income was due to the investment of
the proceeds of our initial and secondary public offerings.

                                        19
<PAGE>

QUARTERLY RESULTS OF OPERATIONS

     Our revenues have increased in all periods presented as a result of the
continuous expansion of our customer base, the sale of additional products and
services to our existing customers and the release of new products and services.
The quarterly results also reflect the respective mergers with Jupiter
Communications and RelevantKnowledge and the acquisition of AdRelevance and,
therefore, are not comparable to prior periods. Our results of operations may
fluctuate significantly in the future as a result of a variety of factors, many
of which are beyond our control.

     The following is a summary of our unaudited quarterly results of operations
for the years ended December 31, 2000 and 1999. You should read these quarterly
data in conjunction with our audited financial statements. You should not view
the results of operations for any period as an indication of the results of
operations for any future period.

<Table>
<Caption>
                                                                    QUARTER ENDED
                               ---------------------------------------------------------------------------------------
                               DEC. 31,   SEPT. 30,   JUNE 30,   MAR. 31,   DEC. 31,   SEPT. 30,   JUNE 30,   MAR. 31,
                                 2000       2000        2000       2000       1999       1999        1999       1999
                               --------   ---------   --------   --------   --------   ---------   --------   --------
                                                        (IN THOUSANDS, EXCEPT PER SHARE DATA)
<S>                            <C>        <C>         <C>        <C>        <C>        <C>         <C>        <C>
Revenues:
  Measurement................  $ 15,043   $ 13,964    $ 12,618   $ 10,204   $  7,569    $ 5,496    $ 4,257    $ 3,178
  Research services..........    15,283      1,955          --         --         --         --         --         --
  Events and other...........     8,154        557          --         --         --         --         --         --
                               --------   --------    --------   --------   --------    -------    -------    -------
Total revenues...............    38,480     16,476      12,618     10,204      7,569      5,496      4,257      3,178
Gross profit.................    19,676     11,655       7,902      5,793      4,077      2,535      2,139      1,458
Loss from operations.........   (42,741)   (12,261)    (10,352)   (10,188)   (16,474)    (4,044)    (2,898)    (2,464)
Net loss applicable to common
  stockholders...............   (37,398)   (10,135)     (7,679)    (8,109)   (14,327)    (2,629)    (2,594)    (2,466)
Basic and diluted net loss
  per share applicable to
  common stockholders........  $  (1.07)  $  (0.47)   $  (0.39)  $  (0.41)  $  (0.75)   $ (0.15)   $ (0.16)   $ (0.19)
</Table>

<Table>
<Caption>
                                                                    QUARTER ENDED
                               ---------------------------------------------------------------------------------------
                               DEC. 31,   SEPT. 30,   JUNE 30,   MAR. 31,   DEC. 31,   SEPT. 30,   JUNE 30,   MAR. 31,
                                 2000       2000        2000       2000       1999       1999        1999       1999
                               --------   ---------   --------   --------   --------   ---------   --------   --------
<S>                            <C>        <C>         <C>        <C>        <C>        <C>         <C>        <C>
Revenues:
  Measurement................      39.1%      84.8%      100.0%     100.0%     100.0%     100.0%     100.0%     100.0%
  Research services..........      39.7       11.9          --         --         --         --         --         --
  Events and other...........      21.2        3.3          --         --         --         --         --         --
                               --------   --------    --------   --------   --------    -------    -------    -------
Total revenues...............     100.0      100.0       100.0      100.0      100.0      100.0      100.0      100.0
Gross profit.................      51.1       70.7        62.6       56.8       53.9       46.1       50.2       45.9
Loss from operations.........    (111.1)     (74.4)      (82.0)     (99.8)    (217.7)     (73.6)     (68.1)     (77.5)
Net loss applicable to common
  stockholders...............     (97.2)%    (61.5)%     (60.9)%    (79.5)%   (189.3)%    (47.8)%    (60.9)%    (77.6)%
</Table>

LIQUIDITY AND CAPITAL RESOURCES

     Since our inception, we have financed our operations primarily through an
initial investment and loan by NPD, the private placement of equity securities,
Jupiter Communication's and RelevantKnowledge's cash on hand at the time of the
respective mergers, cash from operations and the proceeds of public offerings.
On May 12, 1999, we completed the initial public offering of 3,250,000 shares of
our common stock for gross proceeds of $55.3 million, and net proceeds of $49.4
million. On October 29, 1999, we completed a secondary offering of 3,000,000
shares of our common stock. Of the shares offered, Jupiter Media Metrix sold
1,500,000 shares and 1,500,000 shares were sold by existing stockholders. Gross
proceeds to Jupiter Media Metrix were $75.8 million, and net proceeds to Jupiter
Media Metrix were $71.1 million.

     Net cash used in operating activities was $30.8 million for the year ended
December 31, 2000, $6.0 million for the year ended December 31, 1999, and
$411,000 for the year ended December 31, 1998. For the

                                        20
<PAGE>

years ended December 31, 2000 and 1999, net cash used in operating activities
was substantially impacted by our investment in international expansion. The
variance for 2000 compared to 1999 was primarily due to a higher net loss for
the year, due to increased costs for domestic operations and international
expansion.

     Net cash provided by (used in) investing activities was $2.3 million for
the year ended December 31, 2000, $(19.4) million for the year ended December
31, 1999, and $3.1 million for the year ended December 31, 1998. For the year
ended December 31, 2000, cash provided by investing activities primarily relates
to cash received from the merger with Jupiter Communications, net of merger
related expenses, and cash paid for the MMXI Nordic acquisition totaling $27.2
million. This was offset by the purchase of property, plant and equipment of
$20.0 million, purchases of marketable securities of $3.1 million and
$1.8 million for security deposits and restricted cash. For the year ended
December 31, 1999, cash used in investing activities was primarily attributed to
the purchase of investment securities with the proceeds from our public
offerings of common stock pending the use of these proceeds for working capital
purposes along with the purchase of property, plant and equipment. Cash provided
by investing activities for the year ended December 31, 1998 resulted primarily
from the acquisition of $3.2 million of cash in the RelevantKnowledge
transaction.

     Net cash provided by financing activities was $5.3 million for the year
ended December 31, 2000, $114.8 million for the year ended December 31, 1999 and
$3.5 million for the year ended December 31, 1998. Cash provided by financing
activities for the year ended December 31, 2000 was due to contributions from
minority interests of $5.1 million and proceeds received from the exercise of
stock options of $873,000, offset by repayment of long-term debt of $657,000.
Financing activities for the year ended December 31, 1999 resulted from the
receipt of $120.5 million from proceeds of our public offerings, plus $1.3
million in proceeds received from the exercise of warrants and stock options,
offset by the redemption of our redeemable preferred stock for $4.8 million and
repayment of long-term debt of $2.3 million. Cash provided by financing
activities for the year ended December 31, 1998 resulted from the $1.5 million
proceeds from the exercise of warrants and the receipt of $2.0 million on
December 31, 1998 relating to the sale of common stock in January 1999.

     As of December 31, 2000, we had $74.1 million of cash and cash equivalents
and $18.1 million of marketable securities. As of December 31, 2000, our
material capital commitments consisted of improvements to our additional
leasehold space which we anticipate to be approximately $5.0 million. We expect
to invest at least an additional $20.0 million over the next year in our
international operations, in improvements in our technology and data delivery
systems and in connection with lease commitments and related capital
improvements associated with the expansion of our business. We currently
anticipate that we will experience an increase in our capital expenditures and
lease commitments consistent with our anticipated growth in operations,
infrastructure and personnel. In addition, we currently anticipate that we will
continue to experience growth in our operating expenses for the foreseeable
future and that operating expenses will be a material use of our cash resources.

     On October 25, 2001, Jupiter Media Metrix and NetRatings, Inc. entered into
a merger agreement and related loan and security agreement. On February 19,
2002, such agreements were mutually terminated. In addition, Jupiter Media
Metrix announced it would form a special committee of its board of directors to
immediately begin exploring strategic options to strengthen its position in the
marketplace. Jupiter Media Metrix anticipates that its existing cash and cash
equivalents and short-term investments will be sufficient to meet its
anticipated cash needs for working capital and capital expenditures through the
first quarter of 2002. As a result, it will have to raise additional funds or
divest itself of portions of its business. Jupiter Media Metrix cannot be sure
that additional financing or divestitures will be available on terms favorable
to it, or at all. If adequate funds are not available when required, Jupiter
Media Metrix may be forced to curtail or cease its operations.

RISK FACTORS

THERE IS LIMITED INFORMATION UPON WHICH YOU CAN EVALUATE OUR BUSINESS.

     We have been in operation since 1996 as an entity independent from The NPD
Group, Inc. In addition, AdRelevance began selling its products and services in
the fall of 1999 and many of the research services and conferences offered by
Jupiter Communications were first introduced in 1999 and 2000. As a result, we
have a limited operating history upon which you can evaluate the combined
business and the products and services to

                                        21
<PAGE>

be offered by Jupiter Media Metrix. Due to this limited operating history, it is
difficult or impossible for us to predict future results of operations.
Moreover, any evaluation of our business and prospects must be made in light of
the risks and uncertainties frequently encountered by companies in new and
rapidly evolving markets such as ours. Many of these risks and uncertainties are
discussed elsewhere in this section. We cannot assure you that we will be
successful in addressing all of these risks and uncertainties. Our failure to do
so could cause our business and financial results to suffer.

WE HAVE A HISTORY OF OPERATING LOSSES, WHICH MAY CONTINUE FOR THE FORESEEABLE
FUTURE.

     We have incurred substantial costs to create, market and distribute our
products and services, to attract and retain qualified personnel, to make
strategic acquisitions, to expand into international markets and to otherwise
grow our business. As a result, we incurred net losses of approximately $63.3
million in the fiscal year ended December 31, 2000, which includes amortization
of intangibles expense of $46.6 million.

     We intend to invest heavily in new products and services, technology
improvements and international expansion. As a result, we will need to achieve
significant revenue increases to achieve and maintain profitability. Our revenue
growth has slowed in recent months and we may not be able to continue to
effectively expand our business unless revenues continue to grow. The number of
clients or the number of products and services for which our clients subscribe
may grow more slowly than we anticipate or may decrease in the future. In
addition, even if we become profitable, we may not be able to sustain
profitability or increase our profits on a quarterly or annual basis in the
future.

OUR OPERATING RESULTS MAY FLUCTUATE FROM QUARTER TO QUARTER.

     Our revenues, expenses and operating results have varied from quarter to
quarter. Our operating results may continue to vary as a result of a variety of
factors, many of which are beyond our control. These factors include, among
others:

     - the level and timing of new business and renewals of subscriptions to our
       products and services;

     - the announcement or introduction of new products and services by us or
       our competitors;

     - price competition;

     - the amount and timing of costs relating to changes in the size or
       composition of our panels;

     - the amount and timing of operating costs and capital expenditures
       relating to the expansion of our business, particularly our international
       expansion;

     - the levels of attendance and timing of our Internet conferences;

     - changes in the market environment of Internet companies; and

     - the timing of acquisitions and the impact on our operations and our
       operating results.

     Due to all the foregoing factors and the other risks described in this
section, you should not rely on quarter-to-quarter comparisons of our results of
operations as an indication of future performance.

OUR EXISTING AND POTENTIAL CUSTOMERS AND THE COMPANIES WITH WHICH WE HAVE OTHER
BUSINESS RELATIONSHIPS MAY EXPERIENCE ADVERSE BUSINESS CONDITIONS THAT COULD
ADVERSELY AFFECT OUR BUSINESS.

     General economic conditions have caused some of our existing customers to
experience difficulty in supporting their current operations and implementing
their business plans. Existing customers may reduce their spending on our
products and services, or may not be able to discharge their payment and other
obligations to us. Potential customers may be more reluctant to subscribe to our
products and services. The non-payment of amounts due to us from a number of
customers would negatively impact our financial condition. The overall market
for Internet advertising has been characterized in recent quarters by increasing
softness of demand, the reduction or cancellation of contracts, an increased
risk of uncollectible receivables from advertisers, and the reduction of
Internet advertising budgets, especially by Internet-related companies. Our
customers that are Internet-related companies may experience difficulty raising
capital, or may be anticipating such difficulties, and therefore may elect to
scale back the resources they devote to advertising or research, diminishing the
need for our products and services. Our focus on Internet audience measurement,
analysis, intelligence and events may cause us to be disproportionately affected
by the slowdown in this sector

                                        22
<PAGE>

of the economy. Other companies in the Internet industry have depleted their
available capital, and could cease operations or file for bankruptcy protection.
If the current environment for Internet advertising does not improve, our
business, results of operations and financial condition could be materially
adversely affected.

WE DEPEND ON INCREASED SALES OF, AND HIGH RENEWAL RATES FOR, OUR
SUBSCRIPTION-BASED PRODUCTS AND SERVICES.

     Our business and financial results are dependent on our ability to attract
and retain subscribers to our online measurement and research products. In
addition, our business model assumes that we will be able to increase the level
of sales over time to our existing clients. In the past, we have experienced
high renewal rates for our online measurement and research products but these
rates have declined in recent months. Our subscription renewal rates may
continue to decline as a result of a consolidation in our customer base, a
decrease in discretionary spending by our customers or a significant number of
our customers ceasing operations. Our sales to new or existing customers could
also decline as a result of our inability to continue to deliver high-quality
and timely research analysis to our clients, our failure to anticipate and
understand market trends or our inability to develop and update products and
services to meet the changing technological demands of our clients. If our
renewal rate percentage continue to decline or if sales decline, it could have a
material adverse effect on our business, results of operations and financial
condition.

THE INTERNET AUDIENCE MEASUREMENT INDUSTRY IS SUBJECT TO RAPID CHANGE AND
EVOLVING INDUSTRY STANDARDS.

     To date, no Internet audience measurement service has been adopted as the
universally accepted standard. As a result, some of our existing and potential
customers may challenge or refuse to accept our audience measurement reports.
Our customers may also be dissatisfied with our methodology for measuring
Internet audiences or may feel that our panels are not representative of
Internet users. Furthermore, it is possible that another Internet audience
measurement service could be adopted as the industry standard. Several key
industry organizations, including the Internet Advertising Bureau, the Media
Ratings Council, the Advertising Research Foundation and FAST Forward, have
initiatives focusing on appropriate standards for Internet audience measurement.
Our products and services may ultimately not comply with recommended industry
guidelines if we determine that compliance would not be economically feasible or
otherwise not consistent with our business strategy. To the extent that our
measurement approach diverges from the course of action recommended by some or
all of these trade groups, our business, results of operations and financial
condition could be materially and adversely affected.

     In addition to the lack of a universally accepted standard, the audience
measurement business is characterized by rapidly changing technology, numerous
competitive products and services and shifting customer demands and needs. As a
result, our future success in this field depends on our ability to adapt to
rapidly changing technologies, including the tracking of Internet usage through
new technologies, and to improve the features, reliability and timeliness of our
product and service offerings in response to competitive product and service
offerings. In addition, the widespread adoption of new Internet networking
technologies could require us to expend substantial amounts of capital to change
our services or technology infrastructure, thereby increasing the costs of
operating our business. We cannot assure you that we will be able to continue to
offer Internet audience measurement services that satisfy all the information
needs of our existing and potential clients.

OUR RESEARCH AND EVENTS BUSINESSES MAY SUFFER IF WE ARE UNABLE TO ANTICIPATE
MARKET TRENDS OR IF WE FAIL TO PROVIDE INFORMATION THAT IS USEFUL TO OUR
CLIENTS.

     The success of our research and events businesses depends in large part on
our ability to anticipate, research and analyze rapidly changing technologies
and industries, as well as our ability to provide this information in a timely
and cost-effective manner. Internet commerce is relatively new and is undergoing
frequent and dramatic changes, including the introduction of new products and
the obsolescence of others, shifting business strategies and revenue models,
consolidation of businesses, the entry of new companies and high rates of
growth. Because of these rapid and continuous changes in the Internet commerce
markets, we face significant challenges in providing timely analysis and advice.
Many of the industries and areas on which we focus are relatively new, and it is
very difficult to provide predictions and projections as to the future
marketplace, revenue models and competitive factors. If our predictions or
projections prove to be wrong, or if we are unable to continually update our
information, our reputation may suffer and demand for our research

                                        23
<PAGE>

products and services may decline. In addition, many companies have not embraced
the use of the Internet as a medium for commerce and are unclear as to how to
allocate corporate resources effectively. As a result, some companies may
conclude that our research products are not useful to their businesses. If we
are unable to continue to provide credible and reliable information that is
useful to companies engaged in Internet commerce, or to provide this information
in a timely manner, our business and financial results will suffer.

OUR BUSINESS MAY SUFFER IF ONLINE ADVERTISING DOES NOT GROW.

     Our AdRelevance unit specializes in the automated retrieval and delivery of
online advertising data. In addition, many of our research and measurement
products and events are focused on the growth and effectiveness of online
advertising. As a result, our future success will depend in part on an increase
in the use of the Internet as an advertising medium. The Internet advertising
market, however, is relatively new and rapidly evolving, and there is
significant uncertainty about the demand and market acceptance for Internet
advertising. Many of our current or potential customers have little or no
experience using the Internet for advertising purposes. The adoption of Internet
advertising, particularly by entities that have historically relied on
traditional media for advertising, requires the acceptance of a new way of
conducting business. These companies may find Internet advertising to be less
effective for promoting their products and services as compared to traditional
advertising. In addition, most current and potential Web publisher customers
have little or no experience in generating revenues from the sale of advertising
space on their Web sites. In recent quarters, demand for Internet advertising
has slowed. We cannot assure you that the market for Internet advertising will
grow. If the market for Internet advertising does not grow or grows more slowly
than we expect, then our business, results of operations and financial condition
could be materially and adversely affected.

OUR BUSINESS MAY SUFFER IF WE ARE UNABLE TO ATTRACT ATTENDEES, SPONSORS AND
EXHIBITORS TO OUR CONFERENCES.

     Our business and financial results depend in part on our ability to attract
attendees, sponsors and exhibitors to our conferences. We cannot assure you that
we will be able to select topics for our conferences that potential attendees,
sponsors and exhibitors will find timely and interesting. We also cannot assure
you that our competitors will not produce conferences on similar topics or that
we will continue to be able to attract prominent industry leaders to participate
in our conferences. If we are unable to produce compelling events, if we face
increased competition for our conferences or if we are unable to attract
prominent speakers, our conference business will be harmed. In recent months, we
have had to cancel scheduled conferences and the interest in our conferences may
continue to diminish as companies continue to decrease spending that they deem
discretionary. Our business and financial results may also suffer if we are
forced to increase our rate of cancellations of conferences as a result of poor
attendance, inclement weather or some other unexpected event.

OUR BUSINESS MAY SUFFER IF THE USE OF THE INTERNET AS A COMMERCIAL MARKETPLACE
DOES NOT CONTINUE TO GROW.

     Our future success depends on the continued growth of the Internet as a
viable commercial medium. However, the continued growth of the Internet as a
widely-used medium for commerce and communication is uncertain, and this growth
may be inhibited for a number of reasons, including:

     - inadequate network infrastructure;

     - unwillingness of companies and consumers to shift their purchasing from
       traditional vendors to online vendors;

     - security and authentication concerns with respect to the transmission of
       confidential information, such as credit card numbers, over the Internet;

     - unwillingness of companies to invest in the Internet or other evolving
       technologies;

     - privacy concerns, including those related to the ability of Web sites to
       gather user information without the user's knowledge or consent;

     - significant uncertainty about the demand and market acceptance for
       Internet advertising and the lack of standards to measure the
       effectiveness of Internet advertising; or

     - lack of availability of cost-effective, high-speed service.

                                        24
<PAGE>

THE MARKETS IN WHICH WE OPERATE ARE HIGHLY COMPETITIVE, AND SUCH COMPETITION IS
LIKELY TO INCREASE IN THE FUTURE.

     Each of the markets in which we operate is highly competitive. In March
1999, NetRatings and Nielsen Media Research introduced a new Web site ratings
service, Nielsen//NetRatings, which competes directly with many aspects of our
audience measurement services. Nielsen Media Research is the leading provider of
television audience measurement services in the United States and Canada. In
September 1999, NetRatings also entered into a joint venture with ACNielsen
Corp. to develop and maintain audience measurement panels and to market
Nielsen//NetRatings' products and services in international markets. ACNielsen
is a leading provider of market research, information and analysis to consumer
products and services industries and is a provider of television audience
measurement services outside the United States and Canada. Subsequently, VNU
B.V., a leading media and information company, purchased both AC Nielsen and
Nielsen Media Research. We also face competition from NetValue, a public French
company, which has begun providing audience measurement services in Europe and
the United States.

     We also compete indirectly with operators of site-centric and other
consumer-centric measurement systems. Site-centric measurement systems measure
audience visits at a specific Web site by monitoring the Web site's server.
Consumer-centric systems measure the market either in a manner similar to us or
qualitatively through on-line and telephonic interviews. Lastly, we may face
increased competition from individual Web sites that develop an independent
method of measuring their own audience and from other companies that develop
alternative audience measurement technologies to those already provided by us or
our current competitors. In March 2001, DoubleClick Inc. and comScore Networks
announced a joint marketing plan for a new online audience measurement product,
NetScore which uses data gathered from comScore's large database of traffic
information from its opt-in users. NetScore uses a methodology different than
both our measurement model and the site-centric models. We may face
significantly increased competition from this new service if NetScore is able to
take advantage of the significant financial and marketing resources of
DoubleClick and comScore or if NetScore's methodology becomes generally
accepted.

     In the market for Internet commerce-related research products and services,
our principal competitor is Forrester Research, Inc. Numerous other companies
compete with us both domestically and internationally in providing research and
analysis related to a specific industry or geographic area. In addition, we face
increased direct and indirect competition from information technology research
firms, business consulting and accounting firms, electronic and print publishing
companies and equity analysts employed by financial services companies. We also
face strong competition in the business of producing conferences related to
Internet commerce, and an increasing number of companies are sponsoring these
conferences in the United States and abroad. These competitors include
publishing and media companies, research providers, financial services companies
and consulting firms and companies which focus solely on the production of
conferences.

     We expect competition to increase because of the business opportunities
presented by the growth of Internet commerce around the world. Competition may
also intensify as a result of industry consolidation, because of technological
advancements in the way to measure Internet activity or because some of our
competitors may be able to provide additional or complementary services, such as
consulting services. Increased competition may result in reduced operating
margins, loss of market share and diminished value in our services, as well as
different pricing, service or marketing decisions.

     Our current and potential competitors include companies that may have
greater financial, information gathering and marketing resources than we have.
This may allow them to devote greater resources than we can to the promotion of
their brand and to the development and sale of their products and services. We
cannot assure you that we will be able to compete successfully against current
and future competitors.

WE FACE MANY CHALLENGES AS WE CONTINUE TO EXPAND INTERNATIONALLY.

     Our current strategy includes further expansion of our measurement services
and research products, as well as our Internet conferences, outside of the
United States. Our expansion into international markets, however, requires
significant management attention and resources and may negatively impact our
near-term results of operations. For example, the international markets for
audience measurement services have
                                        25
<PAGE>

historically been extremely localized and difficult to penetrate. As a result,
the costs of establishing and maintaining panels in foreign countries has been
and will continue to be substantial. We cannot assure you that we will be able
to develop new products and services based on data obtained in those markets or
that there will be sufficient client demand for these measurement products. In
addition, we cannot assure you that there will be sufficient demand for our
research products and conferences in some of the international markets in which
we promote such products and events.

     Our success in penetrating markets outside of the United States also
depends heavily on our continued ability to develop and to maintain strategic
relationships with local audience measurement or marketing research companies,
as well as local distributors for our research services. These companies assist
us in recruiting and maintaining measurement panels, controlling costs and
managing our international operations and marketing and selling products and
services. Recruiting international partners may become increasingly difficult as
competition in the international markets increases. If we do not succeed in
attracting or retaining our strategic partners or distributors in markets
outside the United States, our business, financial condition and results of
operations could be materially adversely affected.

     In addition, our international operations will be subject to a number of
inherent risks, including:

     - the impact of recessions in economies outside the United States;

     - changes in regulatory requirements;

     - reduced protection for intellectual property rights in some countries;

     - potentially adverse tax consequences;

     - economic and political instability; and

     - fluctuations in currency exchange rates.

     These risks may have a material adverse effect on our business, results of
operations or financial condition.

WE MAY NOT BE ABLE TO ATTRACT AND RETAIN EXPERIENCED PERSONNEL.

     Our success depends in large part on the continued contributions of our
senior management team, research analysts, sales representatives and technical
personnel. However, we face intense competition in hiring and retaining
personnel from, among others, technology and Internet companies, market research
and consulting firms, print and electronic publishing companies and financial
services companies. Many of these firms have substantially greater financial
resources than we do to attract and retain qualified personnel from a limited
pool of attractive candidates. In addition, some people that we may attempt to
hire could be subject to non-competition agreements that could impede our
recruitment efforts. To the extent that we are unable to retain our existing
management, research analysts, sales representatives or technical personnel, or
attract additional personnel that our critical to the operation of our business,
our business and financial results may suffer.

WE MAY NOT BE ABLE TO PROTECT AND ENFORCE OUR INTELLECTUAL PROPERTY RIGHTS.

     We regard the protection of our patents, copyrights, service marks,
trademarks and trade secrets as important to our future success. We rely on a
combination of patent, copyright, trademark, service mark and trade secret laws
and contractual restrictions to establish and protect our proprietary rights. We
cannot assure you, however, that the steps we have taken will be sufficient to
protect our intellectual property from infringement or misappropriation.
Moreover, effective intellectual property protections may not be available in
every country in which we offer our products and services to the extent these
protections are available in the United States.

     We seek to obtain the issuance of patents for our technology, and the
registration of our material trademarks and service marks, in the United States
and in selected other countries. We cannot assure you, however, that all of our
pending or future patent or trademark applications and registrations will be
issued or
                                        26
<PAGE>

granted, or that our patents and trademarks will be upheld as valid if they are
subjected to a challenge. On March 27, 2001, we filed a complaint for patent
infringement against NetRatings, Inc. and NetValue USA, Inc. in federal district
court in the District of Delaware. Our complaint seeks money damages from and a
permanent injunction against both NetRatings and NetValue. We cannot assure you
that we will prevail in this litigation.

     Other parties may assert claims against us that we have misappropriated a
trade secret or infringed a patent, copyright, trademark or other proprietary
right belonging to them. Our use of the brand name "Media Metrix" in Europe had
been challenged by Mediametrie, S.A., a French company that measures audiences
of various media. Rather than engage in a protracted dispute, we elected to have
our European joint venture conduct business under the name "MMXI Europe".
Mediametrie had also challenged our use of the domain name "mediametrix.com".

     Any infringement or related claims, even if not meritorious, could be
costly and time consuming to litigate, may distract management from other tasks
of operating the business and may result in the loss of significant rights or
the ability to operate parts of our business.

WE MAY NOT BE SUCCESSFUL IN EFFECTIVELY PROMOTING OUR BRAND NAMES.

     We believe that maintaining and strengthening our brands is an important
aspect of our business. Our brand names, including "Jupiter Media Metrix",
"Media Metrix", "Jupiter", "AdRelevance" and "JxNetwork", are critical in our
efforts to attract clients and attendees to our conferences. We believe that the
importance of brand recognition will increase due to the increasing number of
competitors entering the market for Internet audience measurement and research
services. Our ability to promote and position our brands depends largely on:

     - the success of our marketing efforts;

     - our ability to provide our customers with high quality products; and

     - our ability to secure rights to our brand names in the major markets in
       which we will be active.

     As described above, our use of the brand name "Media Metrix" in Europe had
been challenged by Mediametrie, S.A., a French company that measures audiences
of various media. We cannot assure you that we will not have any future disputes
with Mediametrie, or any other companies, with respect to the use of any of our
brand names.

     To promote our brands in response to competitive pressures, we may find it
necessary to increase our marketing budget or otherwise increase our financial
commitment to creating and maintaining brand loyalty among our clients. If we
fail to promote and maintain our brands, or incur excessive expenses attempting
to promote and maintain our brand, our business, results of operations and
financial condition will be materially adversely affected.

DISRUPTION OF OUR WEB SITES OR SERVICES DUE TO SECURITY BREACHES AND SYSTEM
FAILURES COULD HARM OUR BUSINESS AND RESULT IN CLIENT CANCELLATIONS.

     The success of each of our businesses depends on the efficient and
uninterrupted operation of our computer and communications systems. Our
measurement services depend on systems that accurately track and monitor
Internet usage and activity and the unimpeded processing of large quantities of
data. In addition, many research services clients pay us so that their employees
can read our research solely on our Web sites and many of our research products
are being increasingly delivered via the Web. Furthermore, the operation of our
business is heavily dependent on systems and networks that connect numerous
offices spread around the world. Our infrastructure and the infrastructure of
our service providers, however, are vulnerable to security breaches, computer
viruses or similar disruptive problems. These systems are also subject to
telecommunications failures, power loss and various other system failures. Any
failure of our current or future systems or networks, whether intentional or
accidental, could impede the processing of data, the delivery of our products
and services, the operation of our Web sites and the day-to-day management of
our business. As a result, these

                                        27
<PAGE>

failures could cause some of our clients to discontinue purchasing some of our
products and services, prevent clients from purchasing our products and services
or attending our events and harm our business reputation.

     In addition, as our company continues to grow and offer additional products
and services around the world, we will need to expand our systems to accommodate
increased data and service additional employees. This could lead to systems
failure or to a corruption of our data and could have a material adverse effect
on our business, results of operations and financial condition.

WE DEPEND ON OUR KEY PERSONNEL.

     Our future success depends on the continued services and on the performance
of our senior management and other key employees, including Gene DeRose, our
Vice Chairman and President; Mary Ann Packo, our Group President, International
Business and Worldwide Marketing; Kurt Abrahamson, our Group President, U.S.
Business and Sales; and Jean Robinson, our Chief Financial and Administrative
Officer. Our current Chairman and Chief Executive Officer, Tod Johnson, who also
serves as the Chairman and Chief Executive Officer of NPD, has announced his
intention to step down as our Chief Executive Officer. He will continue to
remain actively involved in our business matters as Chairman. However, he will
not be able to devote all of his time to our affairs. Mr. Johnson has expressed
his intention to remain our Chief Executive Officer until his successor has been
appointed. We have retained an executive search firm to assist us in our search
for a new Chief Executive Officer.

     The loss of the services of any of our key employees or the inability to
attract and retain a qualified candidate for Chief Executive Officer could have
a material adverse effect on our business, results of operations and financial
condition. We do not maintain any "key person" life insurance policies.

WE MAY NOT BE ABLE TO EFFECTIVELY MANAGE OUR INTERNAL GROWTH.

     We anticipate that future expansion will be necessary in order to grow our
business and to take advantage of new opportunities in the markets for Internet
measurement services and Internet commerce-related research products and
services. In order to succeed, we may need to attract and hire additional
research, sales, technical, administrative, operations and management personnel.
We may also continue to open additional offices in foreign countries. We cannot
assure you that current and planned personnel, systems, procedures and controls
will be adequate to support our future operations. If we fail to effectively
manage our internal growth, our business, results of operations and financial
condition could be materially adversely affected.

WE MAY FAIL TO REALIZE THE ANTICIPATED BENEFITS OF OUR RECENT MERGER WITH
JUPITER COMMUNICATIONS.

     The success of our recent merger with Jupiter Communications will depend,
in part, on our ability to take advantage of the opportunities and synergies
from combining Media Metrix and Jupiter Communications. To realize the
anticipated benefits of this combination, we will have to:

     - Effectively combine and leverage Media Metrix' audience and advertising
       measurement services with the research and events businesses of Jupiter
       Communications;

     - Successfully increase revenues from the cross-promotion and sales of the
       existing products and services of Media Metrix and Jupiter
       Communications;

     - Successfully realize revenues from new products and services;

     - Effectively and efficiently integrate the policies, technology
       infrastructure, procedures and operations of Media Metrix and Jupiter
       Communications; and

     - Successfully retain key employees and attract additional experienced
       personnel to the combined company.

     If members of our management team are not able to develop strategies and
implement a business plan that achieves these objectives, the anticipated
benefits of the merger may not be realized. In addition, we may incur
unanticipated expenses in integrating the businesses of Jupiter Communications
and Media Metrix. If we do not successfully integrate Media Metrix and Jupiter
Communications, or if we incur increased expenses in integrating the two
companies, our business and financial results may suffer and the price of our
common stock could decline.

                                        28
<PAGE>

WE MAY FAIL TO SUCCESSFULLY INTEGRATE FUTURE ACQUISITIONS.

     If appropriate opportunities present themselves, we intend to acquire other
complementary businesses, technologies, services or products. We cannot assure
you, however, that we will be able to complete future acquisitions successfully
or to effectively and efficiently integrate an acquired entity with our current
business. In addition, the key personnel of an acquired company may decide not
to work for us. As a result, these difficulties could disrupt our current
business, distract our management and employees, increase our expenses and
adversely affect our financial results. Furthermore, we may incur debt or issue
equity securities to pay for future acquisitions. The issuance of equity
securities could be dilutive to our existing shareholders' interests.

WE RELY ON TECHNOLOGY LICENSED FROM OTHERS.

     We rely on technologies that we license from third parties. We cannot
assure you that these licenses will not infringe on the proprietary rights of
others. Moreover, these third-party technology licenses may not continue to be
available to us on commercially reasonable terms, if at all. As a result, we may
need to substitute technology of lower quality or performance standards or at
greater cost.

WE MAY BE EXPOSED TO POSSIBLE LIABILITY FOR INFORMATION THAT WE PUBLISH OR
DISSEMINATE, AS WELL AS FOR SUPPLYING INACCURATE INFORMATION TO OUR CLIENTS.

     As a publisher and distributor of original research, market projections and
measurement reports, we face potential liability based on a variety of theories,
including defamation, negligence, copyright or trademark infringement, and other
legal theories based on the publication or distribution of this information.
Claims of this kind, whether brought in the United States or abroad, would
likely divert management time and attention and could result in significant cost
to investigate and defend, regardless of the merit of any of these claims. The
filing of any such claims may also damage our reputation as a high-quality
provider of unbiased, timely analysis and result in client cancellations or
overall decreased demand for our products and services. In addition, if we
become subject to these types of claims and are not successful in our defense,
we may be forced to pay substantial damages. Our insurance may not adequately
protect us against these claims.

     We may also face liability for information that we supply to customers if
the information is inaccurate. The information in our databases, like that in
any database, may contain inaccuracies that our customers may not accept. Any
dissatisfaction by our customers with our measurement or research methodologies
or databases could have a material adverse effect on our ability to attract new
customers and retain existing customers. Any liabilities that we may incur
because of irregularities or inaccuracies in the data we supply to our customers
could materially adversely affect our business, results of operations and
financial condition.

WE FACE RISKS RELATED TO THE STORAGE OF PERSONAL INFORMATION ABOUT OUR
PANELISTS.

     We do not attempt to capture information regarding our panelists' banking,
credit card or password data. This information, however, may come into our
possession. Our panel data are released only in an aggregated format or in a
form not identifiable on an individual basis. However, if someone penetrates our
network security or otherwise misappropriates sensitive data about our
panelists, we could be subject to liability. These liabilities could include
claims for unauthorized purchases with credit card information, impersonation or
other similar fraud claims. They could also include claims for other misuses of
personal information, such as unauthorized marketing purposes. These claims
could result in litigation and could have a material adverse effect on our
business, results of operations and financial condition.

WE FACE RISKS ASSOCIATED WITH POTENTIAL GOVERNMENTAL REGULATION.

     Laws and regulations regarding Internet usage and commerce in the United
States and abroad could decrease the acceptance of the Internet as a commercial
medium and result in decreased demand for our products and services. However,
due to the increasing popularity of the Internet, governmental bodies both in
the United States and abroad are becoming more focused on adopting and proposing
legislation specifically related to the Internet, covering issues such as user
privacy, content restrictions, taxation, advertising, intellectual property
matters and information security. The nature and effect of any recently adopted
or
                                        29
<PAGE>

proposed legislation or regulation cannot be fully determined. Any new
legislation or regulation could have a material adverse effect on our business,
results of operations and financial condition.

     Several states have proposed legislation that would limit the uses of
personal user information gathered using the Internet. These regulations have
required proprietary on-line service and Web site owners to establish privacy
policies. The Federal Trade Commission has also recently settled a proceeding
with one on-line service regarding the manner in which personal information is
collected from users and provided to third parties. The European Union and
Canada have enacted their own privacy regulations that result in limits on the
collection and use of user information. Our compliance with these privacy laws
and their various regulatory requirements could materially affect our
operations.

     Changes to existing laws or the passage of new laws could, among other
things:

     - create uncertainty in the marketplace that could reduce demand for our
       services;

     - limit our ability to collect and to use data from our panels;

     - increase the cost of doing business as a result of litigation costs or
       increased service delivery costs;

     - decrease the efficacy of Internet advertising or impede AdRelevance from
       gathering data for our advertising tracking services; or

     - in some other manner have a material adverse effect on our business,
       results of operations and financial condition.

OUR EXECUTIVE OFFICERS AND DIRECTORS HAVE SUBSTANTIAL CONTROL OVER OUR AFFAIRS.

     Our executive officers and directors and entities affiliated with them in
the aggregate, beneficially owned approximately 22.4% of our common stock as of
March 15, 2001. In particular, The NPD Group, Inc., which is controlled by Tod
Johnson, our Chairman and Chief Executive Officer, owned approximately 12.6% of
our outstanding common stock as of March 15, 2001.

     These stockholders acting together have the ability to exert substantial
influence over all matters requiring approval by our stockholders. These matters
include the election and removal of directors and any merger, consolidation or
sale of all or substantially all of our assets. This concentration of ownership
could have the effect of delaying, deferring or preventing a change in control,
or impeding a merger or consolidation, takeover or other business combination.

WE CANNOT PREDICT OUR FUTURE CAPITAL NEEDS, AND WE MAY NOT BE ABLE TO SECURE
ADDITIONAL FINANCING.

     We may need to raise additional funds in the future to fund our domestic
and international operations, to expand or enhance the range of products and
services we offer or to respond to competitive pressures and/or perceived
opportunities. We cannot be sure that additional financing will be available on
terms favorable to us, or at all. If adequate funds are not available when
required or on acceptable terms, the growth of our business may be hindered and
our business and financial results may suffer.

OUR STOCK HAS EXPERIENCED, AND MAY CONTINUE TO EXPERIENCE, PRICE AND VOLUME
FLUCTUATIONS.

     Our common stock, which is quoted on the NASDAQ National Market, has
experienced significant price and volume fluctuations. These fluctuations are
likely to continue in the future. The market prices of the securities of
Internet-related companies have been especially volatile. Some companies that
have had volatile market prices for their securities have been subject to
securities class action suits filed against them. If a suit were to be filed
against us, regardless of the outcome, it could result in substantial costs and
a diversion of our management's attention and resources. This could have a
material adverse effect on our business, results of operations and financial
condition.

                                        30
<PAGE>

WE HAVE ANTI-TAKEOVER PROVISIONS THAT MAY MAKE IT DIFFICULT FOR A THIRD PARTY TO
ACQUIRE US.

     Provisions of our certificate of incorporation, our bylaws and Delaware law
could make it more difficult for a third party to acquire us, even if doing so
might be beneficial to our stockholders.

ITEM 7A.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

     The carrying values of financial instruments including cash and cash
equivalents, accounts receivable, accounts payable and notes payable,
approximate fair value because of the short maturity of these instruments.

     We have historically had very low exposure to changes in foreign currency
exchange rates, therefore we have not used derivative financial instruments to
manage foreign currency fluctuation risk. We conduct business on a worldwide
basis through our international subsidiaries. As we continue to expand globally,
the risk of foreign currency exchange rate fluctuation may increase. Therefore,
in the future, we may consider utilizing derivative instruments to mitigate such
risks. Currently, we manage our level of exposure by denominating international
sales and payment of related expense in the foreign subsidiaries' local
currency.

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

     The information required by this item is incorporated by reference to the
consolidated financial statements listed in Item 14(a) of Part IV of this Form
10-K.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
FINANCIAL DISCLOSURE.

     None.

                                    PART II

ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT.

     The information regarding directors and executive officers required by Item
10 is incorporated by reference from our definitive proxy statement for our
annual stockholders' meeting to be held on May 16, 2001.

ITEM 11.  EXECUTIVE COMPENSATION.

     The information required by Item 11 is incorporated by reference from our
definitive proxy statement for our annual stockholder's meeting to be held on
May 16, 2001.

ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT.

     The information required by Item 12 is incorporated by reference from our
definitive proxy statement for our annual stockholders' meeting to be held on
May 16, 2001.

ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.

     The information required by Item 13 is incorporated by reference from our
definitive proxy statement for our annual stockholders' meeting to be held on
May 16, 2001.

                                        31
<PAGE>

                                    PART III

ITEM 14.  EXHIBITS, FINANCIAL STATEMENTS SCHEDULES, AND REPORTS ON FORM 8-K

(A)  LIST OF DOCUMENTS FILED AS A PART OF THIS ANNUAL REPORT
     (1)  INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

<Table>
<S>                                                           <C>
            Report of Independent Auditors..................  F-1
            Consolidated Balance Sheets at December 31, 2000
            and 1999........................................  F-2
            Consolidated Statements of Operations for the
            years ended December 31, 2000, 1999 and 1998....  F-3
            Consolidated Statements of Stockholders' Equity
            for the years ended December 31, 2000, 1999 and
            1998............................................  F-4
            Consolidated Statements of Cash Flows for the
            years ended December 31, 2000, 1999 and 1998....  F-5
            Notes to Consolidated Financial Statements......  F-6
</Table>

      (2)  INDEX TO FINANCIAL STATEMENT SCHEDULES

<Table>
<S>                                                           <C>
            Schedule II -- Valuation and Qualifying
            Accounts........................................  S-1
</Table>

     All other schedules for which provision is made in the applicable
accounting regulations of the Securities and Exchange Commission are not
required under the related instructions or are inapplicable and therefore have
been omitted.

(B)  REPORTS ON FORM 8-K

     The Company filed no reports on Form 8-K during the three months ended
December 31, 2000.

(C)  EXHIBITS REQUIRED BY ITEM 601 OF REGULATION S-K

     The Exhibits required to be filed as part of this Annual Report on Form
10-K are listed on the Exhibit Index beginning on page 33. Exhibits 10.22, 10.23
and 10.24 are the management contracts and compensatory plans or arrangements
required to be filed as part of this Annual Report on Form 10-K.

                                        32
<PAGE>

                                LIST OF EXHIBITS

<Table>
<Caption>
 NO.                           DESCRIPTION
 ---                           -----------
<C>    <S>
 2.1   Plan of Merger between Media Metrix and PC Meter L.P. dated
       as of March 31, 1996*
 2.2   Plan of Merger and Reorganization between Media Metrix, Inc.
       and RelevantKnowledge dated as of September 30, 1998*
 2.3   Agreement and Plan of Merger dated as of October 6, 1999, by
       and among Media Metrix, AdRelevance, Merger Sub and the
       stockholders of AdRelevance named therein***
 2.4   Share Purchase Agreement dated February 8, 2000 among SIFO
       Group AB, Osprey Research BV and Media Metrix, Inc.****
 2.5   Agreement and Plan of Merger, dated as of June 26, 2000,
       among Media Metrix, Inc., MMX Acquisition Corp. and Jupiter
       Communications, Inc.*****
 3.1   Amended and Restated Certificate of Incorporation of Media
       Metrix, Inc.*
 3.2   Certificate of Amendment to Amended and Restated Certificate
       of Incorporation*
 3.3   Form of Second Amended and Restated Certificate of
       Incorporation of Media Metrix, Inc.*****
 3.4   Amended and Restated Bylaws of Media Metrix, Inc.*
 3.5   Form of Second Amended and Restated Bylaws of Media Metrix,
       Inc.*****
 4.1   Registration Rights Agreement dated as of November 5, 1998,
       by and among Media Metrix and the Stockholders listed on
       Schedule I thereto*
 4.2   Specimen Stock Certificate*
 4.3   Registration Rights Agreement by and among Media Metrix, GfK
       AG and Ipsos S.A. made as of September 1, 1999**
 4.4   Stock Option Agreement by and between Media Metrix and GfK
       made as of September 1, 1999**
 4.5   Stock Option Agreement by and between Media Metrix and Ipsos
       made as of September 1, 1999**
 4.6   Registration Rights Agreement dated October 8, 1999 by and
       among Media Metrix and the security holders of Media Metrix
       set forth therein***
 4.7   Warrant to purchase common stock held by Silicon Valley
       Bank**
 4.8   Registration Rights Agreement dated March 6, 2000 between
       Osprey Research BV and Media Metrix, Inc.****
 4.9   Media Metrix, Inc. Stock Option Agreement dated March 6,
       2000 between Osprey Research BV and Media Metrix, Inc.****
 4.10  Amendment to Registration Rights Agreement dated March 6,
       2000 among GfK AG, Ipsos SA, Osprey Research BV and Media
       Metrix, Inc.****
 4.11  Jupiter Media Metrix, Inc. Stock Option Agreement dated
       December 27, 2000 by and between Marketing Intelligence
       Corporation and Jupiter Media Metrix.#
 4.12  Jupiter Media Metrix, Inc. Stock Option Agreement dated
       December 27, 2000 by and between Ipsos, S.A. and Jupiter
       Media Metrix.#
10.1   Building Lease between Eagle Insurance Company and The NPD
       Group, Inc. dated as of August 18, 1997*
10.2   Lease Agreement between Carriage House Associates Limited
       Partnership and RelevantKnowledge, Inc. dated as of May 16,
       1997*
10.3   Lease Agreement between 352 P.A.S. Associates and Media
       Metrix, Inc. dated as of March 1, 2000*****
10.4   Lease between WXII/GDM Astor, L.L.C. and Jupiter
       Communications, Inc., dated as of March 17, 2000++
10.5   Sublease between The NPD Group, Inc. and Media Metrix, Inc.
       dated as of March 2000*****
10.6   Sublease between TMP Worldwide, Inc. and Media Metrix, Inc.
       dated as of April 2000*****
</Table>

                                        33
<PAGE>

<Table>
<Caption>
 NO.                           DESCRIPTION
 ---                           -----------
<C>    <S>
10.7   Lease Agreement between Grace Brusseau, individually, and
       Grace Brusseau and Stephen Kay, co-trustees of Testamentary
       Trust of Michael J. Borelli, dba Grazia Investment Company
       and Media Metrix, Inc. dated December 17, 1999*****
10.8   Services Agreement dated as of September 30, 1998 by and
       between Media Metrix and The NPD Group, Inc.*
10.9   License Agreement dated as of November 5, 1998 by and
       between Media Metrix and The NPD Group, Inc.*
10.10  Form of Indemnification Agreement*
10.11  Form of Non-Disclosure Agreement and Confidential
       Information and Invention Assignment Agreement*
10.12  Form of Non-Disclosure Agreement and Confidential
       Information and Invention Assignment Agreement*
10.13  Amended and Restated Management Services Agreement by and
       between Media Metrix, The NPD Group, Inc. and Tod Johnson*
10.14  Media Metrix Stock Option Plan*
10.15  1998 Equity Incentive Plan*
10.16  1998 AdRelevance Stock Option Plan**
10.17  1999 AdRelevance Stock Option Plan**
10.18  Media Metrix, Inc. 2000 Equity Incentive Plan+
10.19  Media Metrix, Inc. 2000 Employee Stock Purchase Plan+
10.20  Media Metrix, Inc. Amended and Restated 2000 Equity
       Incentive Plan*****
10.21  Media Metrix, Inc. Amended and Restated 2000 Employee Stock
       Purchase Plan*****
10.22  Employment Agreement by and between Jupiter Communications,
       Inc. and Gene DeRose.#
10.23  Employment Agreement by and between Jupiter Communications,
       Inc. and Kurt Abrahamson.#
10.24  Employment Agreement by and between Jupiter Communications,
       Inc. and Jean Robinson.#
21     Subsidiaries of the Registrant#
23.1   Consent of Ernst & Young LLP#
23.2   Consent of Ernst & Young LLP#
</Table>

---------------
*      Incorporated by reference to the Company's Registration Statement on Form
       S-1 (File No. 333-72883), filed with the SEC on February 24, 1999, as
       amended.

**    Incorporated by reference to the Company's Registration Statement on Form
      S-1 (File No. 333-88751), filed with the SEC on October 8, 1999, as
      amended.

***   Incorporated by reference to the Company's Current Report on Form 8-K
      filed with the SEC on October 20, 1999.

****  Incorporated by reference to the Company's Current Report on Form 8-K
      filed with the SEC on March 20, 2000.

***** Incorporated by reference to the Company's Registration Statement on Form
      S-4 (File No. 333-42316), filed with the SEC on July 27, 2000, as amended.

+ Incorporated by reference to the Company's Registration Statement on Form S-8
  (File No. 333-39292), filed with the SEC on June 14, 2000.

++    Incorporated by reference to Jupiter Communications, Inc.'s Quarterly
      Report on Form 10-Q (File No. 000-27537), filed with the SEC on May 15,
      2000.

#     Filed herewith.

                                        34
<PAGE>

                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                          JUPITER MEDIA METRIX, INC.

                                                   /s/ ROBERT BECKER
                                          --------------------------------------
                                          By:  Robert Becker
                                          Title: Chief Executive Officer
Date: February 14, 2002

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
registrant and in the capacities indicated on February 14, 2002

<Table>
<Caption>

<S>                                                    <C>

                   /s/ TOD JOHNSON                     Chairman
-----------------------------------------------------
                     Tod Johnson

                                                       Vice Chairman
-----------------------------------------------------
                     Gene DeRose

                  /s/ ROBERT BECKER                    Director and Chief Executive Officer
-----------------------------------------------------  (Principal Executive Officer)
                    Robert Becker

                 /s/ KURT ABRAHAMSON                   Director and President, Jupiter Research
-----------------------------------------------------
                   Kurt Abrahamson

                  /s/ JEAN ROBINSON                    Chief Financial Officer (Principal Financial
-----------------------------------------------------  and Accounting Officer)
                    Jean Robinson

                 /s/ WILLIAM HELMAN                    Director
-----------------------------------------------------
                   William Helman

                  /s/ ROBERT KAVNER                    Director
-----------------------------------------------------
                    Robert Kavner

                    /s/ STIG KRY                       Director
-----------------------------------------------------
                      Stig Kry

                 /s/ JAMES MORTENSEN                   Director
-----------------------------------------------------
                   James Mortensen

                 /s/ ANDREW PARSONS                    Director
-----------------------------------------------------
                   Andrew Parsons

                  /s/ RANDY PAUSCH                     Director
-----------------------------------------------------
                    Randy Pausch
</Table>

                                        35
<PAGE>

                         REPORT OF INDEPENDENT AUDITORS

Stockholders and Board of Directors
Jupiter Media Metrix, Inc.

     We have audited the accompanying consolidated balance sheets of Jupiter
Media Metrix, Inc. (formerly Media Metrix, Inc.) and subsidiaries as of December
31, 2000 and 1999, and the related consolidated statements of operations,
stockholders' equity, and cash flows for each of the three years in the period
ended December 31, 2000. Our audits also included the financial statement
schedule listed in the Index at Item 14(a). These financial statements and
schedule are the responsibility of the Company's management. Our responsibility
is to express an opinion on these financial statements and schedule based on our
audits.

     We conducted our audits in accordance with auditing standards generally
accepted in the United States. Those standards require that we plan and perform
the audit to obtain reasonable assurance about whether the financial statements
are free of material misstatement. An audit includes examining, on a test basis,
evidence supporting the amounts and disclosures in the financial statements. An
audit also includes assessing the accounting principles used and significant
estimates made by management, as well as evaluating the overall financial
statement presentation. We believe that our audits provide a reasonable basis
for our opinion.

     In our opinion, the consolidated financial statements referred to above
present fairly, in all material respects, the consolidated financial position of
Jupiter Media Metrix, Inc. and subsidiaries at December 31, 2000 and 1999, and
the consolidated results of their operations and their cash flows for each of
the three years in the period ended December 31, 2000, in conformity with
accounting principles generally accepted in the United States. Also, in our
opinion, the related financial statement schedule, when considered in relation
to the basic financial statements taken as a whole, presents fairly in all
material respects the information set forth therein.

                                          /s/ ERNST & YOUNG LLP
                                          Ernst & Young LLP

New York, New York
February 7, 2001, except for Note 16 as to which
the date is February 26, 2002

                                       F-1
<PAGE>

                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

                          CONSOLIDATED BALANCE SHEETS

<Table>
<Caption>
                                                                      DECEMBER 31,
                                                              ----------------------------
                                                                  2000            1999
                                                              ------------    ------------
<S>                                                           <C>             <C>
ASSETS
Current assets:
  Cash and cash equivalents.................................  $ 74,133,236    $ 97,363,634
  Marketable securities.....................................    18,080,220      14,877,222
  Receivables:
     Trade, less allowance for doubtful accounts of
       $2,597,000 in 2000 and $500,000 in 1999..............    33,765,623       5,473,299
     Expenditures billable to clients.......................     1,252,762         520,084
                                                              ------------    ------------
  Total receivables.........................................    35,018,385       5,993,383
  Prepaid expenses and other current assets.................     6,819,122         454,072
                                                              ------------    ------------
Total current assets........................................   134,050,963     118,688,311
Property and equipment at cost, net.........................    35,424,739       5,307,667
Intangibles acquired, net...................................   461,615,207      52,948,261
Due from minority interests in consolidated subsidiaries....     2,478,203       1,617,384
Restricted cash and other assets............................    13,406,501         282,801
                                                              ------------    ------------
Total assets................................................  $646,975,613    $178,844,424
                                                              ============    ============
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Liabilities:
  Accounts payable and accrued liabilities..................  $ 32,211,664    $ 10,115,492
  Due to related parties....................................     3,646,291         444,495
  Advance billings to clients...............................    39,923,326       5,125,613
  Current portion of long-term debt.........................       710,845         196,268
                                                              ------------    ------------
Total current liabilities...................................    76,492,126      15,881,868
Deferred rent...............................................     1,659,110              --
Long-term debt..............................................            --         173,387
Commitments and contingencies Stockholders' equity:
  Preferred stock, $.01 par value -- shares authorized:
     10,000,000 in 2000 and 5,000,000 in 1999, none issued
     and outstanding........................................            --              --
  Common stock, $.01 par value -- shares authorized:
     150,000,000 in 2000 and 60,000,000 in 1999; shares
     issued and outstanding: 35,155,362 in 2000 and
     19,681,999 in 1999.....................................       351,554         196,820
  Additional paid-in capital................................   685,807,640     202,031,538
  Accumulated other comprehensive loss......................       (94,646)        (82,424)
  Accumulated deficit.......................................  (101,431,044)    (38,110,438)
  Deferred compensation.....................................   (15,809,127)     (1,246,327)
                                                              ------------    ------------
Total stockholders' equity..................................   568,824,377     162,789,169
                                                              ------------    ------------
Total liabilities and stockholders' equity..................  $646,975,613    $178,844,424
                                                              ============    ============
</Table>

                            See accompanying notes.
                                       F-2
<PAGE>

                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

                     CONSOLIDATED STATEMENTS OF OPERATIONS

<Table>
<Caption>
                                                              YEAR ENDED DECEMBER 31,
                                                    -------------------------------------------
                                                        2000            1999           1998
                                                    ------------    ------------    -----------
<S>                                                 <C>             <C>             <C>
Revenues:
  Measurement.....................................  $ 51,828,704    $ 20,500,127    $ 6,330,485
  Research services...............................    17,238,521              --             --
  Events and other................................     8,710,574              --             --
                                                    ------------    ------------    -----------
Total revenues....................................    77,777,799      20,500,127      6,330,485
Cost of revenues..................................    32,752,051      10,291,392      4,120,569
                                                    ------------    ------------    -----------
Gross profit......................................    45,025,748      10,208,735      2,209,916
Operating expenses:
  Research and development........................    16,077,869       5,044,068      1,382,375
  Sales and marketing.............................    29,427,370       9,116,727      2,888,195
  General and administrative......................    25,881,824       6,755,220      2,715,705
  Amortization of deferred compensation and other
     stock-based compensation.....................     2,551,200       1,060,108        368,550
  Amortization of intangibles.....................    46,629,356       7,312,505        479,000
  Acquired in-process research and development....            --       6,800,000      1,600,000
                                                    ------------    ------------    -----------
Total operating expenses..........................   120,567,619      36,088,628      9,433,825
                                                    ------------    ------------    -----------
Loss from operations..............................   (75,541,871)    (25,879,893)    (7,223,909)
Minority interests................................     5,990,455       1,688,542
Interest and other income, net of interest expense
  of $40,905 in 2000 and $74,660 in 1999..........     6,230,810       2,283,350         65,211
                                                    ------------    ------------    -----------
Net loss..........................................   (63,320,606)    (21,908,001)    (7,158,698)
Preferred dividends...............................            --        (109,195)      (313,738)
                                                    ------------    ------------    -----------
Net loss applicable to common stockholders........  $(63,320,606)   $(22,017,196)   $(7,472,436)
                                                    ============    ============    ===========
Basic and diluted net loss per share applicable to
  common stockholders.............................  $      (2.63)   $      (1.34)   $     (0.98)
                                                    ============    ============    ===========
Shares used in the calculation of basic and
  diluted net loss per share applicable to common
  stockholders....................................    24,083,177      16,445,295      7,618,511
                                                    ============    ============    ===========
</Table>

                            See accompanying notes.
                                       F-3
<PAGE>

                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

                CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY

                  YEARS ENDED DECEMBER 31, 2000, 1999 AND 1998
<Table>
<Caption>
                                                                                          ACCUMULATED
                                        COMMON STOCK         ADDITIONAL      COMMON          OTHER
                                    ---------------------     PAID-IN         STOCK      COMPREHENSIVE    ACCUMULATED
                                      SHARES      AMOUNT      CAPITAL       ISSUABLE         LOSS           DEFICIT
                                    ----------   --------   ------------   -----------   -------------   -------------
<S>                                 <C>          <C>        <C>            <C>           <C>             <C>
BALANCE AT DECEMBER 31, 1997......   6,523,330   $ 65,233   $    281,656   $        --     $     --      $  (8,620,806)
Net loss..........................          --         --             --            --           --         (7,158,698)
Conversion of Series A Convertible
  Preferred Stock.................   2,155,176     21,552      3,978,439            --           --                 --
Conversion of Series B Convertible
  Preferred Stock.................     520,590      5,206      1,494,794            --           --                 --
Issuance of common stock in
  connection with acquisition.....   3,890,825     38,908     10,461,092            --           --                 --
Exercise of warrants..............       8,887         89            197            --           --                 --
Sale of common stock -- 194,380
  shares issuable.................          --         --             --     1,999,831           --                 --
Employee stock options............          --         --      1,933,025            --           --                 --
Amortization of deferred
  compensation....................          --         --             --            --           --                 --
Accrual of redeemable preferred
  stock dividends.................          --         --             --            --           --           (313,738)
                                    ----------   --------   ------------   -----------     --------      -------------
BALANCE AT DECEMBER 31, 1998......  13,098,808    130,988     18,149,203     1,999,831           --        (16,093,242)
Comprehensive loss:
    Net loss......................          --         --             --            --           --        (21,908,001)
    Unrealized loss on marketable
      securities..................          --         --             --            --      (64,134)                --
    Foreign currency
      translation.................          --         --             --            --      (18,290)                --
Total comprehensive loss..........          --         --             --            --           --                 --
Issuance of common stock
  issuable........................     194,380      1,944      1,997,887    (1,999,831)          --                 --
Initial and secondary public
  offering net of $6,727,500 of
  related costs and expenses......   4,750,000     47,500    120,430,000            --           --                 --
Issuance of common stock in
  connection with acquisition.....     697,664      6,977     59,393,023            --           --                 --
Exercise of warrants and stock
  options.........................     941,147      9,411      1,319,465            --           --                 --
Employee stock options............          --         --        325,000            --           --                 --
Amortization of deferred
  compensation....................          --         --             --            --           --                 --
Reversal of deferred compensation
  of options forfeited............          --         --        (98,231)           --           --                 --
Acceleration of vesting on
  options.........................          --         --        515,191            --           --                 --
Accrual of Redeemable Preferred
  Stock dividends.................          --         --             --            --           --           (109,195)
                                    ----------   --------   ------------   -----------     --------      -------------
BALANCE AT DECEMBER 31, 1999......  19,681,999    196,820    202,031,538            --      (82,424)       (38,110,438)
Comprehensive loss:
    Net loss......................          --         --             --            --           --        (63,320,606)
    Unrealized gain on marketable
      securities..................          --         --             --            --       77,263                 --
    Foreign currency
      translation.................          --         --             --            --      (89,485)                --
Total comprehensive loss..........          --         --             --            --           --                 --
Issuance of common stock in
  connection with merger with
  Jupiter Communications, Inc. ...  14,921,856    149,219    477,600,529            --           --                 --
Issuance of common stock in
  connection with other
  acquisitions....................     134,921      1,349      2,752,603            --           --                 --
Exercise of options...............     416,586      4,166        868,970            --           --                 --
Amortization of deferred
  compensation....................          --         --             --            --           --                 --
Employee stock options............          --         --      2,866,000            --           --                 --
Reversal of deferred compensation
  of options forfeited............          --         --       (425,000)           --           --                 --
Acceleration of vesting on
  options.........................          --         --        113,000            --           --                 --
                                    ----------   --------   ------------   -----------     --------      -------------
BALANCE AT DECEMBER 31, 2000......  35,155,362   $351,554   $685,807,640   $        --     $(94,646)     $(101,431,044)
                                    ==========   ========   ============   ===========     ========      =============

<Caption>

                                                       TOTAL
                                      DEFERRED     STOCKHOLDERS'
                                    COMPENSATION      EQUITY
                                    ------------   -------------
<S>                                 <C>            <C>
BALANCE AT DECEMBER 31, 1997......  $         --   $ (8,273,917)
Net loss..........................            --     (7,158,698)
Conversion of Series A Convertible
  Preferred Stock.................            --      3,999,991
Conversion of Series B Convertible
  Preferred Stock.................            --      1,500,000
Issuance of common stock in
  connection with acquisition.....            --     10,500,000
Exercise of warrants..............            --            286
Sale of common stock -- 194,380
  shares issuable.................            --      1,999,831
Employee stock options............    (1,933,025)            --
Amortization of deferred
  compensation....................       368,550        368,550
Accrual of redeemable preferred
  stock dividends.................            --       (313,738)
                                    ------------   ------------
BALANCE AT DECEMBER 31, 1998......    (1,564,475)     2,622,305
Comprehensive loss:
    Net loss......................            --    (21,908,001)
    Unrealized loss on marketable
      securities..................            --        (64,134)
    Foreign currency
      translation.................            --        (18,290)
                                                   ------------
Total comprehensive loss..........            --    (21,990,425)
Issuance of common stock
  issuable........................            --             --
Initial and secondary public
  offering net of $6,727,500 of
  related costs and expenses......            --    120,477,500
Issuance of common stock in
  connection with acquisition.....            --     59,400,000
Exercise of warrants and stock
  options.........................            --      1,328,876
Employee stock options............      (325,000)            --
Amortization of deferred
  compensation....................       544,917        544,917
Reversal of deferred compensation
  of options forfeited............        98,231             --
Acceleration of vesting on
  options.........................            --        515,191
Accrual of Redeemable Preferred
  Stock dividends.................            --       (109,195)
                                    ------------   ------------
BALANCE AT DECEMBER 31, 1999......    (1,246,327)   162,789,169
Comprehensive loss:
    Net loss......................            --    (63,320,606)
    Unrealized gain on marketable
      securities..................            --         77,263
    Foreign currency
      translation.................            --        (89,485)
                                                   ------------
Total comprehensive loss..........            --    (63,332,828)
Issuance of common stock in
  connection with merger with
  Jupiter Communications, Inc. ...   (14,560,000)   463,189,748
Issuance of common stock in
  connection with other
  acquisitions....................            --      2,753,952
Exercise of options...............            --        873,136
Amortization of deferred
  compensation....................     2,438,200      2,438,200
Employee stock options............    (2,866,000)            --
Reversal of deferred compensation
  of options forfeited............       425,000             --
Acceleration of vesting on
  options.........................            --        113,000
                                    ------------   ------------
BALANCE AT DECEMBER 31, 2000......  $(15,809,127)  $568,824,377
                                    ============   ============
</Table>

                            See accompanying notes.
                                       F-4
<PAGE>

                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

                     CONSOLIDATED STATEMENTS OF CASH FLOWS

<Table>
<Caption>
                                                               YEAR ENDED DECEMBER 31,
                                                      -----------------------------------------
                                                          2000           1999          1998
                                                      ------------   ------------   -----------
<S>                                                   <C>            <C>            <C>
OPERATING ACTIVITIES
Net loss............................................  $(63,320,606)  $(21,908,001)  $(7,158,698)
Adjustments to reconcile net loss to net cash used
  in operating activities:
  Charge for acquired in process research and
     development....................................            --      6,800,000     1,600,000
  Loss on disposal of equipment.....................            --         43,123        13,174
  Provision for bad debts...........................       191,000        387,000       160,600
  Depreciation and amortization of property and
     equipment......................................     5,452,158        515,912        65,969
  Amortization of deferred compensation and other
     stock-based compensation.......................     2,551,200      1,060,108       368,550
  Amortization of intangibles.......................    46,629,356      7,312,505       479,000
  Minority Interests................................    (5,990,455)    (1,688,542)           --
  Deferred rent.....................................       188,110             --            --
  Changes in operating assets and liabilities
     Receivables....................................   (15,525,002)    (5,000,046)     (427,652)
     Prepaid expenses and other current assets......       147,750        (44,631)      (13,625)
     Other assets...................................      (534,512)        16,653        28,976
     Accounts payable and accrued liabilities.......    (7,216,828)     7,008,832       657,737
     Advance billings to clients....................     3,457,713      3,727,671       393,581
     Due to related parties.........................     3,201,796     (4,261,330)    3,421,510
                                                      ------------   ------------   -----------
Net cash used in operating activities...............   (30,768,320)    (6,030,746)     (410,878)
                                                      ------------   ------------   -----------
INVESTING ACTIVITIES
Purchase of marketable securities...................    (3,125,735)   (14,941,356)           --
Cash acquired, net of acquisition costs and cash
  paid..............................................    27,246,456        500,511     3,185,112
Additions to property and equipment.................   (19,999,230)    (4,733,977)     (117,489)
Proceeds from the sales of fixed assets.............            --             --         5,300
Security deposits and restricted cash...............    (1,800,188)      (191,336)           --
                                                      ------------   ------------   -----------
Net cash provided by (used in) investing
  activities........................................     2,321,303    (19,366,158)    3,072,923
                                                      ------------   ------------   -----------
FINANCING ACTIVITIES
Repayment on long term debt.........................      (656,610)    (2,321,771)      (19,155)
Proceeds from exercise of warrants and stock
  options...........................................       873,136      1,328,876     1,500,286
Net proceeds from initial and secondary public
  offering..........................................            --    120,477,500            --
Redemption of redeemable preferred stock............            --     (4,788,955)
Contributions from minority interests...............     5,129,636         71,158            --
Sale of common stock................................            --             --     1,999,831
                                                      ------------   ------------   -----------
Net cash provided by financing activities...........     5,346,162    114,766,808     3,480,962
                                                      ------------   ------------   -----------
Effect of exchange rate changes on cash.............      (129,543)       (18,290)
                                                      ------------   ------------   -----------
Net increase (decrease) in cash and cash
  equivalents.......................................   (23,230,398)    89,351,614     6,143,007
Cash and cash equivalents at beginning of year......    97,363,634      8,012,020     1,869,013
                                                      ------------   ------------   -----------
Cash and cash equivalents at end of year............  $ 74,133,236   $ 97,363,634   $ 8,012,020
                                                      ============   ============   ===========
SUPPLEMENTAL INFORMATION
Interest paid.......................................  $     40,905   $     74,660   $    11,374
                                                      ============   ============   ===========
</Table>

                            See accompanying notes.
                                       F-5
<PAGE>

                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. DESCRIPTION OF BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES

  Description of Business

     Jupiter Media Metrix, Inc. (formerly Media Metrix, Inc.), a Delaware
corporation, is a global provider of innovative and comprehensive research and
measurement products and services that analyze the impact of the Internet and
new technologies on commerce and marketing.

  Principles of Consolidation

     The accompanying consolidated financial statements include the accounts of
Jupiter Media Metrix, Inc., its wholly owned subsidiaries Jupiter
Communications, Inc., AdRelevance, Inc., MMXI Nordic and Media Metrix Brasil
Ltda., its 72% owned subsidiary Jupiter Media Metrix Japan KK, its 90% owned
subsidiary Media Metrix Canada Co., its 51% owned subsidiary Media Metrix Pty.
Ltd. Australia and its 50.1% owned subsidiary MMXI Europe, B.V., a Dutch
company. Jupiter Communications, in turn, is consolidated with its wholly owned
subsidiaries, IRG Acquisition Corp., Net Market Makers, Jupiter Communications
Australia Pty Ltd. and Jupiter Communications Scandinavia A.B. MMXI Europe, in
turn, is consolidated with its wholly owned subsidiaries, MMXI UK Limited, MMXI
France E.U.R.L., MMXI (Deutschland) GmbH, MMXI Italia SRL and MMXI Espana. MMXI
Nordic is, in turn, consolidated with its wholly owned subsidiaries,
RelevantKnowledge A.B. and NetCheck A.G. All significant intercompany accounts
and transactions have been eliminated.

  Accounting Estimates

     The preparation of financial statements in conformity with accounting
principles generally accepted in the United States requires management to make
estimates and assumptions that affect the consolidated financial statements and
accompanying notes. Actual results could differ from those estimates.

  Revenue Recognition

     Revenues from the measurement services include syndicated (recurring)
products and services and customized (non-recurring) products and services.
Syndicated products and services are sold on a subscription basis. Revenues for
such products and services are recognized over the term of the related contract
as products or services are provided. Buyers of syndicated products and services
typically are billed in advance for up to the next twelve months. Billings
rendered in advance of products or services being provided are recorded as
"advance billings to clients" in the accompanying consolidated balance sheet.
Revenues for customized products and services are recognized in the period in
which the products or services are provided.

     Revenues from research services are deferred and then recognized
proportionally in operations over the term of the service period, which is
generally up to one year. Unearned amounts are recorded as "advance billings to
clients" in the accompanying consolidated balance sheet.

     Conference and other revenues are reflected in operations in the period in
which the conference occurs or the other services are provided.

  Costs of Revenues

     Costs of revenues consist primarily of panel costs, research analyst costs,
including payroll and travel related to research services, and direct costs
incurred for the conferences. Costs of establishing and maintaining a panel (a
group of consumers who furnish marketing data) are expensed in the year
incurred.

                                       F-6
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

  Commission Expense

     Commissions with the right of charge back are deferred upon the signing of
the contract and amortized to commission expense over the contract period in
which the related revenues are earned and amortized to income. Commission
expense is included within sales and marketing expenses in the accompanying
consolidated statements of operations.

  Research and Development Costs

     Research and development costs primarily consist of costs attributable to
the development of new products and are expensed as incurred.

  Cash and Cash Equivalents

     Cash equivalents consist of highly liquid investments with a maturity date
of three months or less when purchased. Substantially all cash and cash
equivalents are held with four financial institutions at December 31, 2000 and
in three financial institutions at December 31, 1999. Jupiter Media Metrix' cash
is exposed to risk to the extent the balance of the cash accounts exceeds
federally insured limits.

     At December 31, 2000, approximately $5.7 million of restricted cash and
cash equivalents which previously were reflected as current assets have been
reflected as restricted cash and other assets. The restricted cash represents
amounts collateralizing letters of credit issued in lieu of cash security
deposits.

  Marketable Securities

     Jupiter Media Metrix accounts for its investments in accordance with
Statement of Financial Accounting Standard No. 115, "Accounting for Certain
Investments in Debt and Equity Securities." All investments have been classified
as available-for-sale securities as of December 31, 2000 and 1999.
Available-for-sale securities are stated at fair value, with the unrealized
gains and losses reported in accumulated other comprehensive income (loss).
Realized gains and losses and declines other-than-temporary on
available-for-sale securities are included in interest and other income. The
cost of securities sold is based on the specific identification method. Interest
and dividends on securities classified as available-for-sale are included in
interest and other income.

  Concentrations of Credit Risk

     Jupiter Media Metrix' policy is to review a customer's financial condition
prior to extending credit and, generally, collateral is not required. Credit
losses are provided for in the financial statements and have been within
management's expectations. No customer accounted for greater than 10% of our
revenues in 2000, 1999 and 1998.

  Property and Equipment

     Property and equipment are recorded at cost and depreciated or amortized
using the straight-line method over their estimated useful lives which range
from three to five years. Leasehold improvements are amortized over the shorter
of their estimated useful lives or the remaining term of the related lease.

     Jupiter Media Metrix capitalizes internal-use software costs in accordance
with SOP 98-1, "Accounting for the Costs of Computer Software Developed or
Obtained for Internal Use." These costs are amortized using the straight-line
method over the estimated useful lives, which is generally three years and are
classified as property and equipment (see Note 5). At December 31, 2000 and
1999, internal-use software costs were approximately $9,991,000 and $1,476,000,
respectively. Amortization of capitalized internal-use software costs totaled
approximately $956,000 for the year ended December 31, 2000. There was no
amortization of capitalized internal-use software costs recorded for the years
ended December 31, 1999 and 1998.

                                       F-7
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

  Intangible Assets

     Intangibles, primarily consisting of goodwill resulting from acquisitions,
are being amortized by the straight-line method over one to ten years from the
date of acquisition (see Note 3).

  Long-Lived Assets

     The carrying values of intangibles and other long-lived assets are reviewed
for recoverability periodically or whenever events or changes in circumstances
indicate that such amounts have been impaired. Impairment indicators include
among other conditions, cash flow deficits, an historic or anticipated decline
in revenue or operating profit and a material decrease in the fair value of some
or all of the assets. Jupiter Media Metrix uses future undiscounted operating
cash flow analysis to evaluate if there has been any impairment. If such an
impairment exists, the carrying value of the asset is reduced to its estimated
fair value based on discounted cash flows.

  Income Taxes

     Jupiter Media Metrix accounts for income taxes under the provisions of
Statement of Financial Accounting Standard No. 109 (SFAS 109), "Accounting for
Income Taxes." In accordance with SFAS 109, deferred tax assets and liabilities
are recognized for future tax consequences attributable to differences between
financial statement carrying amounts of existing assets and liabilities and
their respective tax bases. Deferred tax assets and liabilities are measured
using enacted rates expected to apply to taxable income in the years in which
those temporary differences are expected to be recovered or settled.

  Fair Value of Financial Instruments

     The carrying amount of cash and cash equivalents, accounts receivable,
accounts payable, accrued expenses and advanced billings to clients approximate
fair value because of the relatively short maturity of these instruments.

  Stock-Based Compensation

     Jupiter Media Metrix accounts for its stock-based employee compensation
agreements in accordance with the provisions of Accounting Principles Board
Opinion No. 25, "Accounting for Stock Issued to Employees" and complies with the
disclosure provisions of Statement of Financial Accounting Standards No. 123,
"Accounting for Stock Based Compensation" ("SFAS 123").

  Foreign Currency Translation

     Local currencies are generally considered to be the functional currency for
operations outside the United States. The translation from the applicable
foreign currencies to U.S. dollars is performed for balance sheet accounts using
current exchange rates in effect at the balance sheet date and for revenue and
expenses accounts using a weighted average exchange rate during the year. The
resulting translation adjustments are reported in accumulated other
comprehensive income (loss). Gains or losses resulting from foreign currency
transactions are included in other income.

  Comprehensive Income (Loss)

     Jupiter Media Metrix adopted Statement of Financial Accounting Standards
No. 130 ("FAS 130"), "Reporting Comprehensive Income," in the first quarter of
fiscal 1999. As required by FAS 130, the Company displays the accumulated
balance of other comprehensive income or loss separately in the equity section
of the consolidated balance sheets. Total comprehensive loss, which is comprised
of net loss and accumulated other comprehensive income (loss), amounted to
approximately $63,333,000 for the year ended December 31, 2000
                                       F-8
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

and approximately $21,990,000 for the year ended December 31, 1999. As of
December 31, 2000, accumulated other comprehensive loss consisted of
approximately a $13,000 gain and a $108,000 loss for the change in unrealized
gain on securities and foreign currency translations, respectively. As of
December 31, 1999, accumulated other comprehensive loss consisted of losses of
approximately $64,000 and $18,000 for the change in unrealized loss on
securities and foreign currency translations, respectively. No other
comprehensive income (loss) existed during 1998.

  Recent Accounting Pronouncements

     In December 1999, the Securities and Exchange Commission staff released
Staff Accounting Bulletin No. 101, "Revenue Recognition" ("SAB 101"), which
provides guidance on the recognition, presentation and disclosure of revenue in
financial statements. The application of SAB 101, as amended, was implemented in
the fourth quarter of 2000 and did not have an impact on Jupiter Media Metrix'
financial position, results of operations or cash flows.

2. BASIC AND DILUTED NET LOSS PER SHARE

     Jupiter Media Metrix computes net loss per share in accordance with the
provisions of Statement of Financial Accounting Standards No. 128, "Earnings per
Share" ("SFAS 128") and SEC Staff Accounting Bulletin No. 98 ("SAB 98"). Under
the provisions of SFAS 128 and SAB 98, basic and diluted net loss per share is
computed by dividing the net loss available to common stockholders for the
period by the weighted average number of common shares outstanding for the
period. The calculation of diluted net loss per share excludes shares of common
stock issuable upon exercise of employee stock options and warrants (see Note
11), as the effect of such exercises would be antidilutive.

     The following sets forth the computation of basic and diluted net loss per
share:

<Table>
<Caption>
                                                         YEAR ENDED DECEMBER 31,
                                                -----------------------------------------
                                                    2000           1999          1998
                                                ------------   ------------   -----------
<S>                                             <C>            <C>            <C>
Numerator:
  Net Loss....................................  $(63,320,606)  $(21,908,001)  $(7,158,698)
  Preferred stock dividends...................            --       (109,195)     (313,738)
                                                ------------   ------------   -----------
  Net Loss applicable to common
     stockholders.............................  $(63,320,606)  $(22,017,196)  $(7,472,436)
                                                ============   ============   ===========
Denominator for basic and diluted loss per
  share weighted average shares...............    24,083,177     16,445,295     7,618,511
                                                ============   ============   ===========
Basic and diluted loss per share applicable to
  common stockholders.........................  $      (2.63)  $      (1.34)  $     (0.98)
                                                ============   ============   ===========
</Table>

3. ACQUISITIONS

     Effective January 1, 2000, Jupiter Media Metrix acquired the internet
audience measurement business operated by SIFO Group AB ("SIFO") in Sweden. The
new company, MMXI Nordic, is a wholly owned subsidiary of Jupiter Media Metrix.
Jupiter Media Metrix acquired all of the outstanding shares of MMXI Nordic in
exchange for $5,692,000 and 52,000 shares of Jupiter Media Metrix' common stock.
In connection with this acquisition, SIFO purchased 8.0% of MMXI Europe,
reducing Jupiter Media Metrix' ownership to 50.1%. The 1999 operations of the
business acquired from SIFO were not significant.

     On September 20, 2000, the Company completed a merger (the "Merger") with
Jupiter Communications, Inc. ("Jupiter Communications") by issuing 14,921,856
shares of Jupiter Media Metrix' common stock in exchange for all of the
outstanding common stock of Jupiter Communications. In addition, Jupiter Media

                                       F-9
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

Metrix assumed all the outstanding stock options to purchase common stock of
Jupiter Communications. The total purchase price of $470.1 million, including
merger related costs and expenses of $6.9 million, was tentatively allocated to
the net assets acquired of $78.5 million, including cash of $44.2 million
(including $4.8 million of restricted cash), and goodwill and other intangibles
of $391.6 million. In addition, deferred compensation of $14.6 million, which
represents the intrinsic value of unvested Jupiter Communications options, was
recorded. In connection with the closing of the Merger, the company changed its
name from Media Metrix, Inc. to Jupiter Media Metrix, Inc.

     In connection with Jupiter Communications' acquisition of Net Market
Makers, Inc. in April 2000, additional consideration was payable based on the
achievement of certain post-closing goals. As of December 31, 2000, Jupiter
Media Metrix has recorded additional goodwill of approximately $4,000,000
related to Net Market Makers having achieved these post-closing goals.

     On October 8, 1999, Jupiter Media Metrix acquired all the outstanding
shares of preferred and common stock of AdRelevance and outstanding options and
warrants to purchase shares of AdRelevance common stock in exchange for 697,664
shares of Jupiter Media Metrix common stock and 222,164 options and warrants to
purchase shares of Jupiter Media Metrix common stock valued at approximately
$59.4 million. The purchase price was allocated as follows: (i) net operating
assets acquired of $1,434,000, including cash of $1,320,000, (ii) acquired
in-process research and development of $6,800,000, (iii) debt of $2,339,000, and
intangibles of $54,324,000, including related costs and expenses of
approximately $819,000. Acquired in-process research and development represents
the value attributed to eight technologies in development using the discounted
value (using a 32% discount rate) of the expected cash flow streams attributed
to those items. Adjustments were made to the expected cash flow streams to
incorporate obsolescence of the technologies, the risk of similar technologies
emerging in the marketplace, and other factors that may reduce the value
realized from the in-process technologies. The technologies relate to tracking
non-banner advertising (valued at $4,911,000), reporting advertising in certain
sections of advertising (valued at $555,000), reporting and comparing
advertising activity among different industries (valued at $551,000), reporting
details of advertising activities of Web media networks (valued at $443,000) and
four other technologies to help enhance tracking, recognition, analysis and/or
reporting of advertising (valued at $340,000). As of the acquisition date, the
aforementioned technologies were 20% to 64% complete and were completed in 2000.

     On October 8, 2000, Jupiter Media Metrix issued an additional 82,921 shares
of common stock and 17,450 options to purchase shares of Jupiter Media Metrix
common stock valued at approximately $995,000 based upon AdRelevance's
achievement of certain post-closing goals in connection with the acquisition of
AdRelevance. This amount has been recorded as additional goodwill.

     On November 5, 1998, Jupiter Media Metrix and an unrelated entity,
RelevantKnowledge, Inc. ("RKI") entered into an agreement and plan of
reorganization whereby RKI was merged into Jupiter Media Metrix. The
stockholders of RKI exchanged all outstanding preferred and common stock of RKI
for 3,890,825 newly issued shares of common stock in Jupiter Media Metrix. The
fair value of the Jupiter Media Metrix common stock issued to the previous
stockholders and option and warrant holders of RKI was approximately
$10,500,000. The purchase price was allocated as follows: (i) net operating
assets acquired of $3,182,000, including cash of $3,185,000, (ii) acquired
in-process research and development of $1,600,000, (iii) debt of $372,000, and
(iv) intangibles of $6,416,000, including related costs and expenses of
approximately $326,000.

     RKI had issued warrants to acquire shares of its common stock in connection
with prior sales of preferred and common stock and convertible secured
promissory notes. Such warrants were exchanged for warrants to purchase 360,907
shares of Jupiter Media Metrix stock and were immediately exercisable as
follows: 266,635 at $0.03 per share, 67,097 at $6.43 per share, 12,055 at $0.19
per share, 7,778 at $2.57 per share and 7,342 at $5.14 per share. All warrants
were exercised in 1998 and 1999. In addition, RKI had issued options to purchase
shares of its common stock to its employees pursuant to a stock option plan.
Such options were exchanged for options to purchase 46,775 shares of Jupiter
Media Metrix common stock at an exercise price of $2.39 per share. All options
are immediately exercisable and expire from 2006 to 2008.

                                       F-10
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

     Acquired in-process research and development represents the value
attributed to three technologies in development using the discounted value
(using a 40% discount rate) of the expected cash flow streams attributed to
those items. Adjustments were made to the expected cash flow streams to
incorporate obsolescence of the technologies, the risk of similar technologies
emerging in the marketplace, and other factors that may reduce the value
realized from the in-process technologies. The three technologies relate to a
data warehousing application (valued at $800,000), a panel management tool
(valued at $770,000), and an automated tracking system (valued at $30,000). As
of the acquisition date, the aforementioned technologies were 25% to 50%
complete and were completed in 1999.

     The estimates used by Jupiter Media Metrix in valuing in-process research
and development were based on assumptions management believes to be reasonable
but which are inherently uncertain and unpredictable. Jupiter Media Metrix'
assumptions may be incomplete or inaccurate, and no assurance can be given that
unanticipated events and circumstances will not occur. Accordingly, actual
results may vary from projected results.

     The above referenced mergers and acquisitions were accounted for using the
purchase method of accounting and the operations of Jupiter Communications,
SIFO, AdRelevance and RKI have been included in the accompanying consolidated
financial statements from the respective dates of the mergers or acquisitions.

     The following table reflects unaudited pro forma results of operations of
Jupiter Media Metrix and Jupiter Communications on the basis that the merger had
taken place on January 1, 1999 and January 1, 2000, and AdRelevance on the basis
that the acquisition had taken place on January 1, 1999:

<Table>
<Caption>
                                                        YEAR ENDED DECEMBER 31,
                                                       --------------------------
                                                          2000           1999
                                                       -----------    -----------
                                                       {(IN THOUSANDS, EXCEPT PER
                                                              SHARE DATA)}
<S>                                                    <C>            <C>
Revenues from sales of services......................   $ 142,824      $  58,587
                                                        =========      =========
Net loss applicable to common stockholders...........   $(138,759)     $(125,179)
                                                        =========      =========
Basic and diluted net loss per share applicable to
  common stockholders................................   $   (3.99)     $   (3.92)
                                                        =========      =========
Shares used in calculation of basic and diluted net
  loss per share applicable to common stockholders...      34,806         31,895
                                                        =========      =========
</Table>

     In management's opinion, the unaudited pro forma results of operations are
not indicative of the actual results that would have occurred had the
AdRelevance acquisition been consummated on January 1, 1999, and the Merger with
Jupiter Communications on January 1, 1999 or on January 1, 2000, or of future
operations of the combined companies under the management of Jupiter Media
Metrix.

                                       F-11
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

4. MARKETABLE SECURITIES

     Marketable securities consist of the following:

<Table>
<Caption>
                                                                   DECEMBER 31, 2000
                                                      -------------------------------------------
                                                                      UNREALIZED
                                                         COST            GAIN         FAIR VALUE
                                                      -----------    -------------    -----------
<S>                                                   <C>            <C>              <C>
AVAILABLE FOR SALE SECURITIES
Corporate bonds.....................................  $11,587,507      $  10,419      $11,597,926
Government securities...............................    4,756,103             --        4,756,103
Asset-backed securities.............................      519,419          1,340          520,759
Certificates of deposit.............................    1,204,062          1,370        1,205,432
                                                      -----------      ---------      -----------
                                                      $18,067,091      $  13,129      $18,080,220
                                                      ===========      =========      ===========
</Table>

<Table>
<Caption>
                                                                   DECEMBER 31, 1999
                                                      -------------------------------------------
                                                                      UNREALIZED
                                                         COST        GAIN/(LOSSES)    FAIR VALUE
                                                      -----------    -------------    -----------
<S>                                                   <C>            <C>              <C>
AVAILABLE FOR SALE SECURITIES
Corporate bonds.....................................  $ 4,244,057      $  (9,015)     $ 4,235,042
Government securities...............................    2,894,240         11,604        2,905,844
Asset-backed securities.............................    6,805,975       (100,170)       6,705,805
Certificates of deposit.............................      997,084         33,447        1,030,531
                                                      -----------      ---------      -----------
                                                      $14,941,356      $ (64,134)     $14,877,222
                                                      ===========      =========      ===========
</Table>

     There were no material realized gains or losses from sales of securities
during the years ended December 31, 2000 and 1999.

5. PROPERTY AND EQUIPMENT

     Property and equipment consist of the following:

<Table>
<Caption>
                                                           DECEMBER 31,
                                                     -------------------------
                                                        2000           1999
                                                     -----------    ----------
<S>                                                  <C>            <C>
Furniture and fixtures.............................  $ 3,181,852    $  475,902
Machinery and equipment............................      839,912            --
Computer equipment.................................   17,543,587     3,307,868
Computer software..................................    9,991,312     1,475,527
Leasehold improvements.............................    9,881,051       609,187
                                                     -----------    ----------
                                                      41,437,714     5,868,484
Less accumulated depreciation and amortization.....    6,012,975       560,817
                                                     -----------    ----------
                                                     $35,424,739    $5,307,667
                                                     ===========    ==========
</Table>

                                       F-12
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

6. INTANGIBLES

     Intangibles consist of the following:

<Table>
<Caption>
                                                          DECEMBER 31,
                                                   ---------------------------
                                                       2000           1999
                                                   ------------    -----------
<S>                                                <C>             <C>
Goodwill.........................................  $511,647,266    $59,339,766
Trademark........................................     2,759,698             --
Other............................................     1,629,104      1,400,000
                                                   ------------    -----------
                                                    516,036,068     60,739,766
Less accumulated amortization....................    54,420,861      7,791,505
                                                   ------------    -----------
                                                   $461,615,207    $52,948,261
                                                   ============    ===========
</Table>

7. ACCOUNTS PAYABLE AND ACCRUED LIABILITIES

     Accounts payable and accrued liabilities consist of the following:

<Table>
<Caption>
                                                           DECEMBER 31,
                                                    --------------------------
                                                       2000           1999
                                                    -----------    -----------
<S>                                                 <C>            <C>
Trade accounts payable............................  $ 6,913,103    $ 3,318,222
Payroll and other related costs...................    9,655,426      2,183,381
Net Market Maker Earnout..........................    4,000,000             --
Accrued taxes other than income...................    6,985,123             --
Panel costs.......................................      161,327      1,296,105
Amounts due minority interests for reimbursement
  of expenses.....................................           --      1,282,231
Other.............................................    4,496,685      2,035,553
                                                    -----------    -----------
                                                    $32,211,664    $10,115,492
                                                    ===========    ===========
</Table>

8. RELATED PARTY TRANSACTIONS

     Effective April 1, 1996 and as amended on September 30, 1998, The NPD
Group, Inc. ("NPD"), the company which founded Jupiter Media Metrix and a major
stockholder, and Jupiter Media Metrix entered into a management services
agreement whereby NPD provides, among other services, Jupiter Media Metrix with
computer processing capacity and certain administrative functions. As
compensation for the services, Jupiter Media Metrix pays NPD, on a monthly
basis, an amount equal to (a) all expenses reasonably incurred by NPD in
performance of its duties under this agreement and (b) 105% of NPD's overhead
allocable to Media Metrix, as defined. The agreement may be terminated by either
party upon 90 days notice, provided NPD may not terminate prior to March 31,
2002. Such charges pursuant to this agreement during the years ended December
31, 2000, 1999 and 1998 amounted to approximately $5,401,000, $2,703,000, and
$6,023,000, respectively. At December 31, 2000, 1999 and 1998, Jupiter Media
Metrix owed approximately $579,000, $444,000 and $4,706,000, respectively, to
NPD for such services. Such amounts are non-interest bearing.

     Jupiter Media Metrix has entered into a Services Agreement with NPD as of
September 30, 1998 and has granted NPD access to its databases for any business
purpose of NPD that is not in direct competition with that of Jupiter Media
Metrix. Jupiter Media Metrix also has granted NPD a non-exclusive license to use
certain computer software owned by it. Under the terms of the Services
Agreement, Jupiter Media Metrix

                                       F-13
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

receives a monthly fee of $2,500 plus expenses. The Services Agreement is
terminable by either party with 120 days notice.

     Jupiter Media Metrix has entered into a license agreement with NPD dated as
of November 5, 1998. NPD has granted to Jupiter Media Metrix an exclusive,
non-transferable worldwide license to use certain NPD software. The fee is
$11,000 per month, payable quarterly.

     AMR Interactive Pty. Ltd. ("AMR"), a minority owner of Media Metrix Pty.
Limited Australia ("Australia"), provides panel recruitment, enumeration and
operation services, and sales and administration services to Australia. Such
charges were approximately $972,000 for the year ended December 31, 2000. As of
December 31, 2000, Jupiter Media Metrix owed AMR approximately $284,000 related
to such services.

     Market Intelligence Corporation ("MiC"), a minority owner of Jupiter Media
Metrix Japan KK ("Japan"), provides panel recruitment, enumeration and operation
services to Japan. Such charges were approximately $2,375,000 for the year ended
December 31, 2000. As of December 31, 2000, Jupiter Media Metrix owed MiC
approximately $610,000 related to such services.

     IPSOS S.A. ("IPSOS") and GfK A.G. ("GfK"), each a minority owner of MMXI
Europe B.V., provide panel recruitment, enumeration and operation services to
MMXI Europe. Such charges were approximately $3,044,000 and $975,000,
respectively, for each of IPSOS and GfK for the year ended December 31, 2000. As
of December 31, 2000, Jupiter Media Metrix owed each of IPSOS and GfK
approximately $1,877,000 and $296,000, respectively, related to such services.

9. LONG-TERM DEBT

     During 1999 and 2000, Jupiter Media Metrix financed the premium due on
their directors and officers liability insurance at a rate of 6% per annum. Such
debt is payable in monthly principal and interest payments of $40,385, and
matures in November 2001. The balance as of December 31, 2000 was $444,237.

     In connection with the Merger with Jupiter Communications, Jupiter Media
Metrix assumed a convertible promissory note that matures on January 7, 2001.
The balance as of December 31, 2000 was $266,608. The promissory note was repaid
in January 2001.

                                       F-14
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

10. INCOME TAXES

     Significant components of Jupiter Media Metrix' deferred income taxes are
as follows:

<Table>
<Caption>
                                                          DECEMBER 31,
                                                  ----------------------------
                                                      2000            1999
                                                  ------------    ------------
<S>                                               <C>             <C>
DEFERRED TAX ASSETS
  Net operating loss carryforwards..............  $ 18,965,000    $ 12,845,000
  Amounts payable to related party..............            --         178,000
  Accrued expenses..............................     4,554,000              --
Accounts receivable reserves....................     1,143,000         200,000
                                                  ------------    ------------
Total deferred tax assets.......................    24,662,000      13,223,000
DEFERRED TAX LIABILITIES
  Deferred compensation.........................     5,443,000              --
  Capitalized software..........................     1,284,000              --
  Amortization..................................     1,260,000              --
                                                  ------------    ------------
Total deferred tax liabilities..................     7,987,000              --
                                                  ------------    ------------
Net deferred tax assets.........................    16,675,000      13,223,000
Valuation allowance for deferred tax assets.....   (16,675,000)    (13,223,000)
Net deferred income taxes.......................  $         --    $         --
                                                  ============    ============
</Table>

     At December 31, 2000, Jupiter Media Metrix has available net operating loss
carryforwards ("NOLs") of approximately $43,103,000 for Federal income tax
purposes that expire in 2012 through 2020. Included in such amounts are
AdRelevance and RKI pre-acquisition NOLs of approximately $3,550,000 and
$11,000, respectively, which expire through 2013. As a result of the RKI
acquisition, under Section 382 of the Internal Revenue Code, utilization of such
NOLs will be limited to approximately $600,000 per year through 2013. Future
benefits, if any, from the acquired NOLs would first reduce the intangibles
acquired and then income tax expense.

     As of the respective acquisition dates, RKI and AdRelevance had net
deferred tax assets of $4,329,000 and $800,000, respectively, with equal
valuation allowances.

     In assessing the realizability of deferred tax assets, management considers
whether it is more likely than not that some portion or all of the deferred tax
assets will not be realized. The ultimate realization of deferred tax assets is
dependent upon the generation of future taxable income during the period in
which the NOL can be utilized and the temporary differences become deductible.
Since Jupiter Media Metrix has incurred losses since inception, Jupiter Media
Metrix has established full valuation allowances for deferred tax assets. The
change in the valuation allowance for the years ended December 31, 2000, 1999
and 1998, excluding acquired valuation allowances, was $3,452,000, 4,053,000 and
$2,670,000, respectively.

11. STOCK OPTIONS

     Jupiter Media Metrix adopted the 1998 Equity Incentive Plan (the "1998
Plan") in November 1998 and, in May 2000, it adopted the 2000 Equity Incentive
Plan which was subsequently amended and restated (the "2000 Plan"). Under the
1998 Plan, Jupiter Media Metrix may award incentive and other non-statutory
stock options, stock appreciation rights, restricted stock and performance stock
units and other stock units which are valued by reference to the value of the
common stock. Jupiter Media Metrix also maintains the Jupiter Media Metrix Stock
Option Plan ("Jupiter Media Metrix Plan"), which provides for the award of up to
519,222 shares of common stock in the form of incentive stock options and
non-statutory stock options. In February 1999, the Board of Directors adopted,
and the shareholders subsequently approved in April 1999, an

                                       F-15
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

amendment to increase the number of shares under the 1998 Plan from 732,400 to
1,318,320. Jupiter Media Metrix is authorized to issue awards of up to 4,000,000
shares of common stock, subject to an automatic adjustment each year as
described in the 2000 Plan.

     In October 1998, Jupiter Media Metrix changed the provisions of all its
outstanding stock options granted prior to such time by removing the requirement
of the occurrence of an initial public offering before such options became
exercisable. This change resulted in a new measurement date. Accordingly,
Jupiter Media Metrix established, as a separate component of stockholders'
equity, deferred compensation (approximately $724,000) equal to the number of
options granted times the difference in their exercise price and $2.30, the
estimated fair value of the common stock at the time of the new measurement
date, and recorded compensation expense in 1998 of approximately $348,000
representing the portion of the deferred compensation which vested through
December 31, 1998. During 2000 and 1999, $90,000 and $123,000 of the deferred
compensation was amortized, respectively.

     On December 3, 1998, Jupiter Media Metrix issued stock options to employees
to purchase 153,072 shares of common stock at $2.39 per share, which was
considered to be the fair value of the common stock at that time. Soon
thereafter, Jupiter Media Metrix issued shares at $10.29 per share (see Note
13); accordingly, for accounting purposes, Jupiter Media Metrix used such per
share value to record an additional deferred compensation charge of $1,209,000
of which approximately $304,000, $361,000 and $20,000 was amortized in 2000,
1999 and 1998, respectively. In addition, during 1999 Jupiter Media Metrix
recorded an additional $325,000 of deferred compensation related to stock
options of which $82,000 and $61,000 of the deferred compensation was amortized
in 2000 and 1999, respectively. Jupiter Media Metrix also recorded a non-cash
compensation charge amounting to approximately $515,000 relating to the
acceleration of the vesting provisions of certain stock options.

     On July 5, 2000, Jupiter Media Metrix issued stock options to employees to
purchase 712,800 shares of common stock at $23.16 per share, below fair market
value, and recorded deferred compensation of $2,866,000. During 2000, $358,000
of the deferred compensation was amortized. In addition, deferred compensation
of $14,560,000, which represents the intrinsic value of unvested Jupiter
Communications options, of which $1,604,000 was amortized during 2000, was
recorded on September 20, 2000 in connection with the merger with Jupiter
Communications.

<Table>
<Caption>
                                         2000                         1999                        1998
                              --------------------------   --------------------------   ------------------------
                               SHARES        WEIGHTED       SHARES        WEIGHTED      SHARES       WEIGHTED
                                UNDER        AVERAGE         UNDER        AVERAGE        UNDER       AVERAGE
                               OPTION     EXERCISE PRICE    OPTION     EXERCISE PRICE   OPTION    EXERCISE PRICE
                              ---------   --------------   ---------   --------------   -------   --------------
<S>                           <C>         <C>              <C>         <C>              <C>       <C>
Balance beginning of year...  1,838,816       $ 1.26         696,130       $ 1.26       283,093       $0.17
Grants......................  1,630,321        21.10       1,047,320        32.62       373,219        1.97
Exercises...................   (416,586)        2.09         (70,519)        1.19            --          --
Forfeitures.................   (404,844)       19.55         (56,279)        2.97        (6,957)       2.30
Options issued in connection
  with acquisitions.........  4,086,674        14.05         222,164         3.77        46,775        2.39
                              ---------                    ---------                    -------
Balance, end of year........  6,734,381        17.50       1,838,816        19.38       696,130        1.26
                              =========                    =========                    =======
Exercisable at end of
  year......................  1,802,803       $ 9.48         354,663       $ 1.17       133,242       $0.39
                              =========                    =========                    =======
Weighted-average fair value
  of options issued during
  the period................                  $17.74                       $23.07                     $3.42
</Table>

                                       F-16
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

     The following tables summarize information about stock options outstanding
at December 31, 2000:

<Table>
<Caption>
                                 OPTIONS OUTSTANDING                  OPTIONS EXERCISABLE}
                      -----------------------------------------   ----------------------------
                                                    WEIGHTED                       WEIGHTED
                                  AVERAGE LIFE      AVERAGE                        AVERAGE
EXERCISE PRICE RANGE   OPTIONS     (IN YEARS)    EXERCISE PRICE   EXERCISABLE   EXERCISE PRICE
--------------------  ---------   ------------   --------------   -----------   --------------
<S>                   <C>         <C>            <C>              <C>           <C>
$ 0.02 -  0.23          191,204       7.1             0.16           146,853         0.14
  0.33 -  0.56          447,205       4.2             0.49           402,853         0.49
  1.85 -  3.71        1,265,559       5.9             2.68           598,628         2.58
  6.23 -  9.95          737,477       8.3             7.64           123,951         6.24
 11.25 - 19.36          819,802       8.1            14.69           204,269        14.70
 20.50 - 36.75        2,676,715       9.3            26.43           178,469        28.58
 37.00 - 44.75          271,371       9.0            40.73            57,212        40.88
 45.00 - 51.80          325,048       8.7            45.35            90,568        45.35
                      ---------                                    ---------
                      6,734,381       8.3            17.50         1,802,803         9.48
                      =========                                    =========
</Table>

  Fair Value Disclosures

     Pro forma information regarding net loss and net loss per share is required
by SFAS 123, which also requires that the information be determined as if
Jupiter Media Metrix has accounted for its stock options under the fair value
method of that statement. The fair value for those options granted prior to
Jupiter Media Metrix' public offering was estimated using the minimum value
method with the following assumptions: no dividend yield, weighted-average
expected life of the option of five years, and risk-free interest rates of 5.7%,
6.2% and 6.1% for the years ended December 31, 1998, 1999 and 2000,
respectively.

     For those options granted after Jupiter Media Metrix became a public entity
an expected volatility factor of 98% and 97% was used for the Black-Scholes
option pricing model for the years ended December 31, 2000 and 1999,
respectively. The Black-Scholes option valuation model was developed for use in
estimating the fair value of traded options that have no vesting restrictions
and are fully transferable. In addition, the option valuation model requires the
input of highly subjective assumptions included the expected stock price
volatility. Because Jupiter Media Metrix' stock options have characteristics
significantly different from those of traded options, and because changes in the
subjective input assumptions can materially affect the fair value estimate, in
management's opinion, the existing models do not necessarily provide a reliable
single measure of the fair value of its stock options.

     For purposes of pro forma disclosures, the estimated fair value of the
options is amortized to expense over the options' vesting period. Jupiter Media
Metrix' pro forma financial information is as follows:

<Table>
<Caption>
                                                      YEAR ENDED DECEMBER 31,
                                            -------------------------------------------
                                                2000            1999           1998
                                            ------------    ------------    -----------
<S>                                         <C>             <C>             <C>
Net loss applicable to common stockholders
  as reported.............................  $(63,320,606)   $(22,017,196)   $(7,472,436)
                                            ============    ============    ===========
Pro forma.................................  $(69,957,689)   $(22,973,184)   $(7,487,969)
                                            ============    ============    ===========
Net loss applicable to common stockholders
  per share:
As reported...............................  $      (2.63)   $      (1.34)   $     (0.98)
                                            ============    ============    ===========
Pro forma.................................  $      (2.90)   $      (1.40)   $     (0.98)
                                            ============    ============    ===========
</Table>

                                       F-17
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

12. LEASE COMMITMENTS

     Jupiter Media Metrix leases office space in the United States and other
countries. At December 31, 2000, the future minimum lease payments under
non-cancelable operating leases with initial or remaining lease terms in excess
of one year are as follows:

<Table>
<S>                                                       <C>
Year ending December 31:
2001....................................................  $ 8,135,000
2002....................................................    8,536,000
2003....................................................    8,905,000
2004....................................................    8,021,000
2005....................................................    6,978,000
Thereafter..............................................   56,245,000
                                                          -----------
                                                          $96,820,000
                                                          ===========
</Table>

     Future minimum lease payments have not been reduced by future minimum
sublease rentals of $142,000 under operating leases. Rent expense approximated
$3,000,000, $861,000 and $356,000 for the years ended December 31, 2000, 1999
and 1998, respectively.

13. STOCKHOLDERS' EQUITY

     As disclosed in Note 3, Jupiter Media Metrix issued 14,921,856 and 134,921
shares of common stock in connection with the merger with Jupiter Communications
and acquisitions of MMXI Nordic and AdRelevance in 2000, 697,664 shares of
common stock in connection with its acquisition of AdRelevance in 1999 and
3,890,825 shares of common stock in connection with its acquisition of RKI in
1998.

     On January 4, 1999, Jupiter Media Metrix issued to a foreign investor
194,380 shares of common stock at a purchase price per share of $10.29, for an
aggregate purchase price of approximately $2,000,000, pursuant to a stock
purchase agreement. Jupiter Media Metrix had received the proceeds from this
transaction on December 31, 1998 and had recorded "common stock issuable" in the
1998 consolidated balance sheet.

     In May 1999, Jupiter Media Metrix consummated an initial public offering
(the "IPO") of 3,000,000 shares of common stock at a price of $17 per share. The
underwriters in connection with the IPO exercised their over-allotment option to
purchase an additional 250,000 shares from Jupiter Media Metrix and 200,000
shares from existing shareholders at a price of $17 per share. The total net
proceeds to Jupiter Media Metrix amounted to approximately $49,383,000 after
deducting the underwriters' discount and related expenses of $5,867,000.

     In October 1999, Jupiter Media Metrix consummated a secondary offering of
3,000,000 shares of common stock at a price of $50.50 per share. Of the
3,000,000 shares sold, 1,500,000 shares were sold by Jupiter Media Metrix and
1,500,000 shares were sold by existing stockholders. The net proceeds to Jupiter
Media Metrix were $71,095,000 after deducting the underwriters' discount and
related expenses.

     Jupiter Media Metrix has reserved 9,446,831 shares of common stock for
issuance upon the exercise of all outstanding options and warrants at December
31, 2000.

14. INTERNATIONAL OPERATIONS

     In September 1999, Jupiter Media Metrix entered into a venture with GfK AG
and IPSOS SA to form MMXI Europe B.V. In March 2000, in connection with Jupiter
Media Metrix' acquisition of MMXI Nordic, SIFO became a shareholder of MMXI
Europe. Jupiter Media Metrix owns 50.1%, GfK owns 19.9%, IPSOS owns 22.0% and
SIFO owns 7.9% of MMXI Europe.

                                       F-18
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

     In December 1999, Jupiter Media Metrix formed Media Metrix Japan KK, now
known as Jupiter Media Metrix Japan KK, as a wholly owned subsidiary. Effective
January 1, 2000, Jupiter Media Metrix entered into a venture with Marketing
Intelligence Corporation ("MiC") to own and operate Jupiter Media Metrix K.K. in
Japan. Jupiter Media Metrix owns 72% and MiC owns 28% of the company.

     In January 2000, Jupiter Media Metrix entered into a venture with ComQUEST
Research Inc. ("ComQUEST") to form Media Metrix Canada Co. Pursuant to the terms
of the agreement, Jupiter Media Metrix owns 90% and ComQUEST owns 10% of the
venture.

     Effective January 1, 2000, Jupiter Media Metrix acquired the Internet
audience measurement business operated by SIFO in Sweden (see Note 3).

     Effective January 1, 2000, Jupiter Media Metrix entered into a venture with
IPSOS to form JMXI Latin America B.V., a Netherlands company. Jupiter Media
Metrix owns 51% and IPSOS owns 49% of the company.

     In March 2000, Jupiter Media Metrix entered into a venture with AMR to form
Media Metrix Pty. Limited Australia. Jupiter Media Metrix owns 51% and AMR owns
49% of the company.

     In September 2000, Jupiter Media Metrix entered into a venture with IHA
Institut fur Marketanalysen ("IHA"), an affiliate of GfK to form MMXI
Switzerland GmbH, a Swiss company. Jupiter Media Metrix owns 19.9% and IHA owns
80.1% of the company.

     In connection with the formation of each of the international ventures,
Jupiter Media Metrix granted each of its venture partners an option, subject to
certain conditions, to exchange such partners shares in the respective ventures
for shares of Jupiter Media Metrix common stock. If any partner elects to
exercise its option to convert its shares into shares of Jupiter Media Metrix
common stock, Jupiter Media Metrix will need to record additional goodwill in an
amount equal to the difference between the then fair market value of the shares
of Jupiter Media Metrix' common stock, multiplied by the number of shares issued
and the net book value of the joint venture of which such partner is a
shareholder attributable to such partner.

15. SEGMENT INFORMATION

     Prior to the merger with Jupiter Communications on September 20, 2000,
Jupiter Media Metrix operated in one business segment, providing Internet and
digital measurement products and services.

     Currently, Jupiter Media Metrix operates in three business segments. Its
business units include Media Metrix and AdRelevance, which offer clients a broad
range of products and services that measure audience, advertising commerce and
new media usage on the Internet and other digital media; Jupiter Research, which
provides business-to-business and business-to-consumer clients with strategic
analysis and insights, including industry trends, forecasts and best practices,
all backed by proprietary data; and Jupiter Events, a leading provider of
conferences focusing on the global digital economy.

                                       F-19
<PAGE>
                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

           NOTES TO CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)

     The following table presents information about Jupiter Media Metrix'
operating segments for the year ended December 31, 2000:

<Table>
<Caption>
                                                       MEDIA METRIX AND    JUPITER     JUPITER EVENTS
                                            TOTAL        ADRELEVANCE       RESEARCH      AND OTHER
                                          ---------    ----------------    --------    --------------
                                                             (IN THOUSANDS)}
<S>                                       <C>          <C>                 <C>         <C>
Revenues................................  $  77,778        $51,829         $17,238         $8,711
Cost of revenues........................     32,752         20,955           7,181*         4,616
                                          ---------        -------         -------         ------
Gross Profit............................     45,026        $30,874          10,057         $4,096
                                                           =======         =======         ======
Non-allocated expenses..................   (108,347)
                                          ---------
Net loss................................  $ (63,321)
</Table>

---------------
* All research personnel compensation is charged to Jupiter Research. No
  allocation is made for research personnel involved in Jupiter Events.

     The following table presents information about Jupiter Media Metrix by
geographic area for the year ended December 31, 2000:

<Table>
<Caption>
                                                            REVENUES
                                                         --------------
                                                         (IN THOUSANDS)
<S>                                                      <C>
United States..........................................     $66,656
International..........................................      11,122
                                                            -------
                                                            $77,778
                                                            =======
</Table>

     There were no material international revenues for the year ended December
31, 1999 and 1998. There are no significant long-lived assets outside the United
States. In addition, Jupiter Media Metrix has not allocated its assets to the
reportable segments.

16. SUBSEQUENT EVENTS

     On October 25, 2001, Jupiter Media Metrix and NetRatings, Inc. entered into
a merger agreement and related loan and security agreement. On February 19,
2002, such agreements were mutually terminated. In addition, Jupiter Media
Metrix announced it would form a special committee of its board of directors to
immediately begin exploring strategic options to strengthen its position in the
marketplace. Jupiter Media Metrix anticipates that its existing cash and cash
equivalents and short-term investments will be sufficient to meet its
anticipated cash needs for working capital and capital expenditures through the
first quarter of 2002. As a result, it will have to raise additional funds or
divest itself of portions of its business. Jupiter Media Metrix cannot be sure
that additional financing or divestitures will be available on terms favorable
to it, or at all. If adequate funds are not available when required, Jupiter
Media Metrix may be forced to curtail or cease its operations. The accompanying
financial statements do not reflect any adjustments that might result if Jupiter
Media Metrix were unable to continue as a going concern.

                                       F-20
<PAGE>

                                                                     SCHEDULE II

                  JUPITER MEDIA METRIX, INC. AND SUBSIDIARIES

                       VALUATION AND QUALIFYING ACCOUNTS

<Table>
<Caption>
                                                  ADDITIONS
                                    BALANCE AT    CHARGED TO      CHARGED                        BALANCE
                                    BEGINNING     COSTS AND      TO OTHER                        AT END
DESCRIPTION                         OF PERIOD      EXPENSES     ACCOUNTS(A)    DEDUCTIONS(B)    OF PERIOD
-----------                         ----------    ----------    -----------    -------------    ---------
                                                               (IN THOUSANDS)
<S>                                 <C>           <C>           <C>            <C>              <C>
Reserves and allowances deducted
  from assets to which they apply:
ALLOWANCE FOR DOUBTFUL ACCOUNTS
Year ended December 31, 2000......     $500          $191         $2,330           $424          $2,597
Year ended December 31, 1999......     $220          $387             --           $107          $  500
Year ended December 31, 1998......     $100          $161             --           $ 41          $  220
</Table>

---------------
(a) Reserves acquired in connection with mergers and acquisitions.

(b) Write-offs of amounts against allowance provided.

                                       S-1