UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

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FORM 10-K/AAmendment No. 1

|(Mark One)                                  |                                                                                         
|------------------------------------------- | ----------------------------------------------------------------------------------------
|ý                                           | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934    
|For the fiscal year ended December 31, 2004
|OR                                         
|o                                           | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Commission file number: 000-27907

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NETRATINGS, INC.(Exact name of Registrant as specified in its charter)

|Delaware(State or other jurisdiction of incorporation of organization)                                                       |  | 77-0461990(I.R.S. Employer Identification No.)
|---------------------------------------------------------------------------------------------------------------------------- |  | ----------------------------------------------
|120 West 45th Street, 35th Floor
New York, New York(Address of principal executive offices)                                  |  | 10036(Zip Code)                               
|Registrant's telephone number, including area code:(212) 703-5900Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Name of each exchange on which registeredNone

None


Securities registered pursuant to Section 12(g) of the Act: Common Stock(Title of Class)

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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 for 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 ý    No o

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 information statements incorporated by reference in Part III of this Form 10-K or any amendment to
this Form 10-K. ý

Indicate by check mark whether the Registrant is an accelerated filer (as defined in Rule 12b-2 of the
Act). Yes ý    No o

The aggregate market value of the voting stock held by non-affiliates of the Registrant, based on the closing price of the Registrant's Common Stock
as quoted on the Nasdaq National Market on June 30, 2004, was $213,658,858.

The
number of shares of the Registrant's Common Stock outstanding as of February 28, 2005 was 35,794,154.

DOCUMENTS INCORPORATED BY REFERENCE

Parts of the definitive proxy statement for the Registrant's 2005 Annual Meeting of Stockholders, which is to be filed with the Commission pursuant to
Regulation 14A not later than 120 days after the end of the fiscal year covered by this Report, are incorporated by reference into Part III of this Report.



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Explanatory Note

NetRatings, Inc. (the "Company") is filing Amendment No. 1 to its Annual Report on Form 10-K for the year ended
December 31, 2004, which was filed with the Securities and Exchange Commission (the "SEC" or the "Commission") on March 16, 2005, to amend such report for the following reasons:

The
Company previously disclosed in its Annual Report on Form 10-K for the year ended December 31, 2004 that it intended to include management's report on
internal control over financial reporting and the related attestation report of the Company's independent registered public accounting firm, required under Section 404 of the Sarbanes-Oxley Act
of 2002 ("Sarbanes-Oxley") and the related SEC rules and regulations, in an amendment to its Annual Report on Form 10-K. The filing of this Amendment No. 1 is in accordance
with the SEC's exemptive order in SEC Release No. 34-50754, which provided qualified issuers with a 45-day extension for filing management's report and the related
attestation. The Company has recently completed its analysis, documentation and testing of its system of internal control over financial reporting and has prepared its report on the effectiveness of
its internal control over financial reporting. In addition, the Company's independent registered public accounting firm, Ernst & Young LLP, has completed its audit and report on management's
assessment of its internal control over financial reporting.

Based
on the foregoing, the following items are amended:



No
other information included in the Annual Report on Form 10-K is amended by this Form 10-K/A. Unaffected items have not been repeated in this
Form 10-K/A and the Company has not updated the disclosure made in this Form 10-K/A to reflect events occurring after the filing of the original Annual Report on
Form 10-K filed on March 16, 2005.

ITEM 9A.    CONTROLS AND PROCEDURES

Disclosure Controls and Procedures

The Company's management, with the participation of the Company's Chief Executive Officer and Chief Financial Officer, has evaluated the effectiveness of the
Company's disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the
"Exchange Act")) as of the end of the period covered by this report. Based on such evaluation, the Company's Chief Executive Officer and Chief Financial Officer have concluded that, as of the end of
such period, the Company's disclosure controls and procedures are effective. Notwithstanding the foregoing, a control system, no matter how well designed and operated, can provide only reasonable, not
absolute, assurance that it will detect or uncover failures within the Company to disclose material information otherwise required to be set forth in the Company's periodic reports.

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Internal Control over Financial Reporting

MANAGEMENT'S ANNUAL REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act
Rules 13a-15(f) and 15d-15(f). Under the supervision and with the participation of our management, including our principal executive officer and principal financial
officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the framework in Internal ControlIntegrated Framework issued by the
Committee of Sponsoring Organizations of the Treadway Commission. Based on our evaluation under the framework in Internal ControlIntegrated Framework, our management concluded that our
internal control over financial reporting was effective as of December 31, 2004.

Because
of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future
periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Our
independent registered public accounting firm, Ernst & Young LLP, audited management's assessment of the Company's internal control over financial reporting as stated in their
report, which is set forth below.

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The
Board of Directors and Shareholders of
NetRatings, Inc.

We
have audited management's assessment, included in the accompanying Management's Annual Report on Internal Control over Financial Reporting, that NetRatings, Inc. maintained
effective internal control over financial reporting as of December 31, 2004, based on criteria established in Internal ControlIntegrated Framework issued by the Committee of
Sponsoring Organizations of the Treadway Commission (the COSO criteria). NetRatings, Inc.'s management is responsible for maintaining effective internal control over financial reporting and for
its assessment of the effectiveness of internal control over financial reporting. Our responsibility is to express an opinion on management's
assessment and an opinion on the effectiveness of the company's internal control over financial reporting based on our audit.

We
conducted our audit in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to
obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control
over financial reporting, evaluating management's assessment, testing and evaluating the design and operating effectiveness of internal control, and performing such other procedures as we considered
necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

A
company's internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of
financial statements for external purposes in accordance with generally accepted accounting principles. A company's internal control over financial reporting includes those policies and procedures
that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide
reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and
expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide

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reasonable
assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company's assets that could have a material effect on the financial statements.

Because
of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future
periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

In
our opinion, management's assessment that NetRatings, Inc. maintained effective internal control over financial reporting as of December 31, 2004, is fairly stated, in
all material respects, based on the COSO criteria. Also, in our opinion, NetRatings, Inc. maintained, in all material respects, effective internal control over financial reporting as of
December 31, 2004, based on the COSO criteria.

We
also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), the 2004 consolidated financial statements of
NetRatings, Inc. and our report dated March 14, 2005 expressed an unqualified opinion thereon.

ERNST &
YOUNG LLP

New
York, New York
April 22, 2005

Internal Control over Financial Reporting

There have not been any changes in the Company's internal control over financial reporting (as such term is defined in Rules 13a-15(f) and
15d-15(f) under the Exchange Act) during the fourth quarter of 2004 that have materially affected, or are reasonably likely to materially affect, the Company's internal control over
financial reporting.

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PART IV

ITEM 15.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

(a)(3)  Exhibits



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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.

| |  | NETRATINGS, INC.
| |  | ----------------
| |  | By:             

Date:
April 29, 2005

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 and on
the dates indicated:

|Signature                                 |  | Title                                                                                                                              |  | Date          
|----------------------------------------- |  | ---------------------------------------------------------------------------------------------------------------------------------- |  | --------------
|                                          |  |                                                                                                                                    |  |               
|/s/WILLIAM PULVERWilliam Pulver           |  | Chief Executive Officer, President and Director (Principal Executive Officer)                                                      |  | April 29, 2005
|/s/TODD SLOANTodd Sloan                   |  | Executive Vice President Corporate Development, Chief Financial Officer and Secretary (Principal Financial and Accounting Officer) |  | April 29, 2005
|/s/JOHN A. DIMLINGJohn A. Dimling         |  | Chairman of the Board                                                                                                              |  | April 29, 2005
|/s/MICHAEL P. CONNORSMichael P. Connors   |  | Director                                                                                                                           |  | April 29, 2005
|/s/DAVID H. HARKNESSDavid H. Harkness     |  | Director                                                                                                                           |  | April 29, 2005
|/s/ARTHUR F. KINGSBURYArthur F. Kingsbury |  | Director                                                                                                                           |  | April 29, 2005
|/s/THOMAS A. MASTRELLIThomas A. Mastrelli |  | Director                                                                                                                           |  | April 29, 2005
|/s/D. SCOTT MERCERD. Scott Mercer         |  | Director                                                                                                                           |  | April 29, 2005
|/s/JAMES M. O'HARAJames M. O'Hara         |  | Director                                                                                                                           |  | April 29, 2005
|/s/JERRELL W. SHELTONJerrell W. Shelton   |  | Director                                                                                                                           |  | April 29, 2005

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EXHIBIT INDEX

|Exhibit
Number |  | Exhibit Title                                                                                                                                                                     
|-------------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|23.1           |  | Consent of Independent Registered Public Accounting Firm.                                                                                                                         
|31.1           |  | Certificate of Chief Executive Officer pursuant to Rule 13a-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
|31.2           |  | Certificate of Chief Financial Officer pursuant to Rule 13a-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

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