<PAGE>   1
 
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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
 
                             ---------------------

                                   FORM 10-Q/A

                             ---------------------
<TABLE>
<C>               <S>
   (MARK ONE)
      [X]         QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D) OF
                  THE SECURITIES EXCHANGE ACT OF 1934
                  FOR THE QUARTER ENDED SEPTEMBER 30, 1998
                                               OR
      [  ]        TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF
                  THE SECURITIES EXCHANGE ACT OF 1934
                  FOR THE TRANSITION PERIOD FROM ____________ TO ____________
</TABLE>
 
                        COMMISSION FILE NUMBER: 0-20135
 
                         INTERMEDIA COMMUNICATIONS INC.
             (Exact name of registrant as specified in its charter)
 
<TABLE>
<S>                                            <C>
                   DELAWARE                                      59-2913586
       (State or other jurisdiction of                        (I.R.S. Employer
        incorporation or organization)                     Identification Number)
</TABLE>
 
                             3625 QUEEN PALM DRIVE
                              TAMPA, FLORIDA 33619
                    (Address of principal executive offices)
 
                                 (813) 829-0011
                                Telephone Number
 
                             ---------------------
 
     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  [X]                      No  [ ]
 
          As of November 10, 1998, there were 48,597,754 shares of the
                     Registrant's Common Stock outstanding.
 
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<PAGE>   2
 
                         INTERMEDIA COMMUNICATIONS INC.
 
                                     INDEX
 
<TABLE>
<CAPTION>
                                                                       PAGE
                                                                       NO.
                                                                       ----
<S>      <C>                                                           <C>
                      PART I.   FINANCIAL INFORMATION

ITEM 1.  FINANCIAL STATEMENTS (UNAUDITED):
         Condensed Consolidated Statements of Operations -- Three and
         nine months ended September 30, 1998 (restated) and 1997....     3

         Condensed Consolidated Balance Sheets -- September 30, 1998
         (restated) and December 31, 1997............................     4

         Condensed Consolidated Statements of Cash Flows -- Nine
         months ended September 30, 1998 (restated) and 1997.........     5

         Notes to Condensed Consolidated Financial Statements........     6
 
ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
         AND RESULTS OF OPERATIONS...................................    17

                       PART II.   OTHER INFORMATION
 
ITEM 1.  LEGAL PROCEEDINGS...........................................    34
 
ITEM 2.  CHANGES IN SECURITIES.......................................    34
 
ITEM 3.  DEFAULTS UPON SENIOR SECURITIES.............................    34
 
ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.........    35
 
ITEM 5.  OTHER INFORMATION...........................................    35
 
ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K............................    35
 
SIGNATURES...........................................................    37
</TABLE>
 
                                        2
<PAGE>   3
 
                         PART I. FINANCIAL INFORMATION
 
ITEM 1.  FINANCIAL STATEMENTS
 
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
                CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
 
<TABLE>
<CAPTION>
                                                   THREE MONTHS ENDED               NINE MONTHS ENDED
                                              -----------------------------   -----------------------------
                                              SEPTEMBER 30,   SEPTEMBER 30,   SEPTEMBER 30,   SEPTEMBER 30,
                                                  1998            1997            1998            1997
                                              -------------   -------------   -------------   -------------
                                                RESTATED                        RESTATED
                                               SEE NOTE 2                      SEE NOTE 2
                                                                       (UNAUDITED)
                                                        (IN THOUSANDS, EXCEPT SHARE INFORMATION)
<S>                                           <C>             <C>             <C>             <C>
Revenues:
  Local network services....................   $    43,778     $    11,814     $   115,648     $    25,457
  Enhanced data services....................        47,585          30,843         126,790          54,831
  Interexchange services....................        71,552          27,637         199,049          80,877
  Integration services......................        29,438             952          77,882           4,152
                                               -----------     -----------     -----------     -----------
                                                   192,353          71,246         519,369         165,317
Expenses:
  Network operations........................        83,778          49,032         243,337         116,295
  Facilities administration and
     maintenance............................        14,935           9,985          48,503          21,409
  Cost of goods sold........................        19,014             503          49,923           2,537
  Selling, general and administrative.......        59,482          25,004         162,231          64,983
  Depreciation and amortization.............        54,574          16,100         145,565          34,274
  Charge-off of purchased in-process R&D....            --          60,000          63,000          60,000
  Business restructuring, integration and
     other charges..........................         1,791              --          51,872              --
                                               -----------     -----------     -----------     -----------
                                                   233,574         160,624         764,431         299,498
                                               -----------     -----------     -----------     -----------
Loss from operations........................       (41,221)        (89,378)       (245,062)       (134,181)
  Other income (expense):
  Interest expense..........................       (53,942)        (17,689)       (151,101)        (39,895)
  Other income..............................         9,310           6,736          26,078          16,691
                                               -----------     -----------     -----------     -----------
Loss before extraordinary item..............       (85,853)       (100,331)       (370,085)       (157,385)
Extraordinary loss on early extinguishment
  of debt...................................            --         (43,834)             --         (43,834)
                                               -----------     -----------     -----------     -----------
Net loss....................................       (85,853)       (144,165)       (370,085)       (201,219)
Preferred stock dividends and accretions....       (30,647)        (13,895)        (68,118)        (27,118)
                                               -----------     -----------     -----------     -----------
Net loss attributable to common
  stockholders..............................   $  (116,500)    $  (158,060)    $  (438,203)    $  (228,337)
                                               ===========     ===========     ===========     ===========
Basic and diluted loss per common share
  before extraordinary item.................   $     (2.48)    $     (3.41     $    (10.45)    $     (5.60)
Extraordinary loss..........................            --           (1.31)             --           (1.33)
                                               -----------     -----------     -----------     -----------
Net loss per common share...................   $     (2.48)    $     (4.72)    $    (10.45)    $     (6.93)
                                               ===========     ===========     ===========     ===========
Weighted average number of shares
  outstanding...............................    47,041,191      33,479,460      41,948,399      32,925,462
                                               ===========     ===========     ===========     ===========
</TABLE>
 
                            See accompanying notes.
 
                                        3
<PAGE>   4
 
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
                     CONDENSED CONSOLIDATED BALANCE SHEETS
 
<TABLE>
<CAPTION>
                                                              SEPTEMBER 30, 1998     DECEMBER 31, 1997
                                                              -------------------    ------------------
                                                                   RESTATED
                                                                  SEE NOTE 2
                                                                             (UNAUDITED)
                                                              (IN THOUSANDS, EXCEPT SHARE INFORMATION)
<S>                                                           <C>                    <C>
                                                ASSETS
Current Assets:
    Cash and cash equivalents...............................      $  597,534             $  756,923
    Restricted investments..................................           8,800                  6,853
    Accounts receivable, less allowance for doubtful
      accounts of $23,473 in 1998 and $4,251 in 1997........         145,075                 58,579
    Prepaid expenses and other current assets...............          19,864                  6,122
                                                                  ----------             ----------
         Total current assets...............................         771,273                828,477
    Telecommunications equipment............................       1,399,896                545,380
      Less accumulated depreciation.........................        (176,930)               (81,534)
                                                                  ----------             ----------
    Telecommunications equipment, net.......................       1,222,966                463,846
    Intangible assets, net..................................       1,043,595                138,028
    Investment in Shared Technologies Fairchild Inc.........              --                403,571
    Other assets............................................          57,658                 41,048
                                                                  ----------             ----------
         Total assets.......................................      $3,095,492             $1,874,970
                                                                  ==========             ==========
 
              LIABILITIES, REDEEMABLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT)
 
Current liabilities:
    Accounts payable........................................      $  100,385             $   53,630
    Other accrued expenses..................................          92,677                 20,130
    Current portion of long-term debt and capital lease
      obligations...........................................          10,804                  7,471
                                                                  ----------             ----------
         Total current liabilities..........................         203,866                 81,231
Long-term debt and capital lease obligations................       2,284,794              1,244,872
Series B redeemable exchangeable preferred stock and accrued
  dividends, $1.00 par value; 600,000 shares authorized;
  369,432 and 334,420 shares issued and outstanding in 1998
  and 1997, respectively....................................         358,962                323,146
Series D junior convertible preferred stock and accrued
  dividends, $1.00 par value; 69,000 shares authorized;
  54,129 and 69,000 shares issued and outstanding in 1998
  and 1997, respectively....................................         133,419                169,722
Series E junior convertible preferred stock, $1.00 par
  value; 87,500 shares authorized; 64,892 and 80,000 shares
  issued and outstanding in 1998 and 1997, respectively.....         159,785                196,008
Series F junior convertible preferred stock and accrued
  dividends, $1.00 par value; 92,000 shares authorized;
  80,000 shares issued and outstanding in 1998..............         195,583                     --
Stockholders' equity (deficit):
    Preferred stock, $1.00 par value; 1,111,500 and
      1,203,500 shares authorized in 1998 and 1997,
      respectively, no shares issued........................              --                     --
    Series C preferred stock, $1.00 par value; 40,000 shares
      authorized, no shares issued..........................              --                     --
    Common stock, $.01 par value; 150,000,000 and 50,000,000
      shares authorized in 1998 and 1997, respectively;
      48,248,049 and 34,890,600 shares issued and
      outstanding in 1998 and 1997, respectively............             482                    175
    Additional paid-in capital..............................         579,774                244,114
    Accumulated deficit.....................................        (814,209)              (376,006)
    Deferred compensation...................................          (6,964)                (8,292)
                                                                  ----------             ----------
         Total stockholders' deficit........................        (240,917)              (140,009)
                                                                  ----------             ----------
         Total liabilities, redeemable preferred stock and
           stockholders' equity (deficit)...................      $3,095,492             $1,874,970
                                                                  ==========             ==========
</TABLE>
 
                            See accompanying notes.
 
                                        4
<PAGE>   5
 
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
                CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
 
<TABLE>
<CAPTION>
                                                                         NINE MONTHS ENDED
                                                              ---------------------------------------
                                                              SEPTEMBER 30, 1998   SEPTEMBER 30, 1997
                                                              ------------------   ------------------
                                                                   RESTATED
                                                                  SEE NOTE 2
                                                                            (UNAUDITED)
                                                                          (IN THOUSANDS)
<S>                                                           <C>                  <C>
OPERATING ACTIVITIES
  Net loss..................................................      $(370,085)           $(201,219)
  Adjustments to reconcile net loss to net cash used in
    operating activities:
      Extraordinary loss on early extinguishment of debt,
         noncash portion....................................             --                5,869
      Depreciation and amortization.........................        148,839               35,502
      Amortization of deferred compensation.................          1,328                1,095
      Non cash items included in business restructuring,
         integration and other charges......................         22,345                   --
      Accretion of interest on notes payable and capital
         leases.............................................         63,546               27,712
      Imputed interest related to the business
         acquisitions.......................................          6,164                   --
      Charge-off of purchased in-process R&D................         63,000               60,000
      Provision for doubtful accounts.......................         14,538                3,834
      Changes in operating assets and liabilities:
         Accounts receivable................................        (47,821)             (25,648)
         Prepaid expenses and other current assets..........         (4,045)              (1,483)
         Other assets.......................................         (6,321)                  --
         Accounts payable...................................          9,101                8,777
         Accrued expenses...................................         12,967                3,685
                                                                  ---------            ---------
Net cash used in operating activities.......................        (86,444)             (81,876)
INVESTING ACTIVITIES
  Purchases of restricted investments.......................         (1,139)                  --
  Maturities of restricted investments......................             --               30,805
  Purchase of businesses, net of cash acquired..............       (465,694)            (150,085)
  Maturities of short-term investments......................             --                5,550
  Purchases of telecommunications equipment.................       (338,116)            (178,732)
                                                                  ---------            ---------
Net cash used in investing activities.......................       (804,949)            (292,462)
FINANCING ACTIVITIES
  Proceeds from sale of preferred stock, net of issuance
    costs...................................................        193,747              454,992
  Proceeds from issuance of long-term debt, net of issuance
    costs...................................................        537,303              362,993
  Exercise of stock warrants and options....................          7,657                2,861
  Principal payments on long-term debt and capital lease
    obligations.............................................         (6,703)            (164,953)
                                                                  ---------            ---------
Net cash provided by financing activities...................        732,004              655,893
Increase (decrease) in cash and cash equivalents............       (159,389)             281,555
Cash and cash equivalents at beginning of period............        756,923              189,546
                                                                  ---------            ---------
Cash and cash equivalents at end of period..................      $ 597,534            $ 471,101
                                                                  =========            =========
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Assets purchased under capital lease obligations............      $ 435,771            $   6,172
Common stock issued in purchase of business.................        225,925                   --
Interest paid...............................................         47,180               11,759
Preferred stock issued as dividends on preferred stock......         35,015               23,499
Common stock issued as dividends on preferred stock.........         19,012                   --
Warrants and options issued in purchase of business.........             --               19,380
Accretion of preferred stock................................          2,206                  869
</TABLE>
 
                            See accompanying notes.
 
                                        5
<PAGE>   6
 
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                                  (UNAUDITED)
 
NOTE 1.  BASIS OF PRESENTATION
 
     The accompanying unaudited condensed consolidated financial statements have
been prepared in accordance with generally accepted accounting principles for
interim financial information and with the instructions to Form 10-Q and Article
10 of Regulation S-X. Accordingly, they do not include all of the information
and footnotes required by generally accepted accounting principles for complete
financial statements. In the opinion of management, all adjustments (consisting
of normal recurring accruals) necessary to present fairly the information set
forth therein have been included. The accompanying condensed consolidated
financial statements should be read in conjunction with the consolidated
financial statements and footnotes included in the Annual Report on Form 10-K as
amended of Intermedia Communications Inc. ("Intermedia" or the "Company") for
the year ended December 31, 1997.
 
     Operating results for the three and nine month periods ended September 30,
1998 are not necessarily an indication of the results that may be expected for
the year ending December 31, 1998.
 
STOCK SPLIT
 
     All share and per share information presented herein and in the Company's
Condensed Consolidated Financial Statements has been retroactively restated to
reflect a two-for-one stock split of the Company's Common Stock, par value $.01
per share ("Common Stock"), on June 15, 1998, paid in the form of a stock
dividend, to holders of record on June 1, 1998.
 
RECENTLY ISSUED ACCOUNTING STANDARDS
 
     In June 1997, the Financial Accounting Standards Board issued Statement of
Financial Accounting Standards No. 131, Disclosures about Segments of an
Enterprise and Related Information ("SFAS 131"), which supersedes Financial
Accounting Standards No. 14. SFAS 131 uses a management approach to report
financial and descriptive information about a Company's operating segments.
Operating segments are revenue-producing components of the enterprise for which
separate financial information is produced internally for the Company's
management. SFAS 131 is effective for fiscal years beginning after December 31,
1997, but is not required to be applied to interim financial statements in the
initial year of its application. Management is currently assessing the impact of
this standard. However, management believes the Company operates as a single
segment, telecommunication services provider.
 
NOTE 2.  RESTATEMENT
 
     The management of the Company and the staff ("Staff") of the Securities and
Exchange Commission (the "Commission") have had discussions with respect to the
methods used to value purchased in-process research and development ("R&D")
recorded and written off at the date of acquisition. As a result of these
discussions, the Company has modified the methods used to value purchased
in-process R&D in connection with the Company's 1998 acquisition of Shared
Technologies Fairchild Inc. ("Shared"). Initial calculations of value of the
purchased in-process R&D were based on, among other things, the after-tax cash
flows attributable to each project, and the selection of an appropriate rate of
return to reflect the risk associated with the stage of completion of each
project. Revised calculations of the value of the purchased in-process R&D are
based on adjusted after-tax cash flows that give explicit consideration to the
Staff's views on purchased in-process R&D as set forth in its September 15, 1998
letter to the American Institute of Certified Public Accountants and the Staff's
comments for the Company to consider (i) the stage of completion of the
purchased in-process R&D at the dates of acquisition, (ii) contributions of the
Company's own distinct and unique proprietary advantages, and (iii) the
estimated total project costs of the purchased in-process R&D in arriving at the
valuation amount. As a result of this modification, the Company has decreased
the amount of the purchase price of Shared allocated to purchased in-process R&D
from $85.0 million to $63.0 million for

                                        6
<PAGE>   7
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
the three months ended March 31, 1998. As a result, the Company increased
goodwill by $22.0 million. In addition, as a further result of the discussions
with the Staff referred to above, the Company reallocated $51.0 million of the
purchase price of Shared, originally reported as goodwill, to customer lists and
work force. The shorter lives associated with these identifiable intangible
assets, coupled with the effects on goodwill of the restatement for in-process
R&D, resulted in an increase in amortization expense of $0.9 million and $2.7
million for the three and nine month periods ended September 30, 1998,
respectively. The Company also reduced the business restructuring charge for the
three month period ended September 30, 1998 by $9.1 million, resulting from a
contract negotiation during the third quarter. Finally, the Company increased
the business restructuring charge for the three month period ended September 30,
1998 by $1.3 million and reduced the business restructuring charge for the nine
month period ended September 30, 1998 by $1.2 million principally as a result of
deferring the recognition of consulting costs to the period in which they were
incurred.
 
     The restatement resulted in the following impact on the Company's
previously reported results of operations for the three and nine month periods
ended September 30, 1998 (in thousands except per share data).
 
<TABLE>
<CAPTION>
                                                              THREE MONTHS     NINE MONTHS
                                                                  ENDED           ENDED
                                                              SEPTEMBER 30,   SEPTEMBER 30,
                                                                  1998            1998
                                                              -------------   -------------
<S>                                                           <C>             <C>
Net loss:
  As previously reported....................................    $(92,796)       $(399,673)
  Adjustment to purchased in-process R&D....................          --           22,000
  Adjustment related to additional amortization of
     intangible assets......................................        (912)          (2,737)
  Adjustment to business restructuring, integration and
     other charges..........................................       7,855           10,325
                                                                --------        ---------
  As restated...............................................    $(85,853)       $(370,085)
                                                                ========        =========
Net loss per share -- basic and diluted
  As previously reported                                        $  (2.62)       $  (11.15)
  Adjustment to purchased in-process R&D....................          --             0.52
  Adjustment related to additional amortization of
     intangible assets......................................       (0.02)           (0.06)
  Adjustment to business restructuring, integration and
     other charges..........................................        0.16             0.24
                                                                --------        ---------
  As restated...............................................    $  (2.48)       $  (10.45)
                                                                ========        =========
</TABLE>
 
NOTE 3.  BUSINESS ACQUISITIONS
 
     On March 10, 1998, the Company completed its acquisition of Shared, a
shared tenant communications services provider. For convenience, the operating
results of Shared are included in the Company's consolidated financial
statements commencing on January 1, 1998. The effect on the Company's net loss
from including the operating results of Shared from January 1, 1998 was not
material. Imputed interest of $5.1 million was recorded based on the cash
consideration paid after the effective date of the acquisition in the first
quarter of 1998 and the cost for Shared was reduced accordingly. Aggregate
consideration for the acquisition was approximately $589.8 million in cash, plus
the retirement of $175.6 million in Shared's long-term debt, and acquisition
related expenses of $16.7 million. The acquisition was accounted for by the
purchase method of accounting, with the purchase price allocated to the fair
value of assets acquired and liabilities assumed, principally goodwill.
 
                                        7
<PAGE>   8
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
     The purchase price allocation was as follows (in thousands):
 
<TABLE>
<S>                                                           <C>
Purchase price..............................................  $782,151
  Less:
     Interest expense adjustment............................     5,130
     Estimated fair value of Shared net assets acquired less
       assumed liabilities..................................    51,245
                                                              --------
Excess of purchase price over fair value of net assets
  acquired..................................................  $725,776
                                                              ========
</TABLE>
 
     The allocation of purchase price to goodwill and identifiable intangibles
and estimated lives are (in thousands):
 
<TABLE>
<CAPTION>
                                                                VALUE      AMORTIZATION
                                                              ALLOCATED   PERIOD IN YEARS
                                                              ---------   ---------------
<S>                                                           <C>         <C>
Developed technology........................................  $100,000          10
Tradename...................................................    10,000           2
In-process R&D..............................................    63,000          --
Goodwill....................................................   501,776          20
Customer lists..............................................    48,000          10
Work force..................................................     3,000          10
</TABLE>
 
     The amount allocated to in-process R&D ($63.0 million) was recorded as a
one-time charge to operations in the accompanying consolidated statements of
operations because the technology was not fully developed and had no future
alternative use. The developed technology was comprised of an intelligent
infrastructure which integrated a host of telecommunications systems, including
infrastructure (network hardware and software), service provider networks, and
inter-building communications networks. The acquired in-process R&D represents
the development of technologies associated with creating infrastructure and the
associated systems so that the Company can offer a wide range of data
telecommunications services. These proprietary projects include the development
of a multi-service access platform ("MSAP"). The MSAP will enable the client
provisioning of multiple data services as well as the realization of Shared's
existing voice services. A brief description of the three categories of
in-process R&D projects is presented below:
 
     - Access Technology Development.  These R&D projects are related to the
       development of access technology, including copper connectivity and
       deployment, DSL technology development and development of T-1 interfaces.
       These projects were valued at approximately $47 million. As of the
       transaction date, the Company believed that the overall project was
       approximately 80% complete. At the date of acquisition, the expected
       costs to complete the project were approximately $0.8 million in 1998 and
       $1.0 million in 1999.
 
     - R&D Related to Networking and Networking Management.  These R&D projects
       are related to the development of systems related to networking
       management, and were valued at approximately $15 million. As of the
       transaction date, the Company believed that the overall project was
       approximately 70% complete. At the date of acquisition, the expected
       costs to complete the project were approximately $0.3 million in 1998 and
       $0.3 million in 1999.
 
     - Advanced Networking.  These R&D projects are related to the development
       of advanced networking functions, and were valued at approximately $1
       million. As of the transaction date, the Company believed that the
       overall project was approximately 25% complete. At the date of
       acquisition, the expected costs to complete the project were
       approximately $0.1 million in 1998 and $0.1 million in 1999.
 
     The distinction between developed technology and acquired in-process R&D is
basically the difference between legacy voice technologies and the emerging data
technologies that are required by Intermedia's high-

                                        8
<PAGE>   9
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
end corporate users; these are very different technologies from a
telecommunications perspective. The completion of the in-process R&D will enable
Shared to provide new data services (asynchronous transfer mode, frame relay,
Internet, and others) through Shared's existing architecture. Prior to the
acquisition, Shared's services portfolio did not include data products.
Historically, Shared could provide its customer base with local and long
distance voice services and customer premise equipment products. However, Shared
lost data revenue opportunities to its competitors.
 
     While material progress has been made on these projects, significant risk
still is associated with their completion. If these projects are unsuccessful,
their expected contribution to revenues and profits will not materialize.
 
     The amortization period for the customer lists was determined based on
historical customer data, including customer retention and average sales per
customer. The basis for the life assigned to assembled workforce was annual
turnover rates.
 
     On March 31, 1998, the Company acquired the Long Distance Savers group of
companies (collectively, "LDS"), a regional interexchange carrier. The operating
results of LDS for the one day of ownership during the first quarter of 1998 are
considered immaterial. The operating results of LDS are included in the
Company's consolidated financial statements commencing on April 1, 1998.
Aggregate consideration for the acquisition was approximately $15.7 million in
cash, plus 5,359,748 shares of the Company's Common Stock valued at
approximately $137.2 million, the retirement of $15.1 million of LDS's long-term
debt, and acquisition related expenses of $2.4 million. The acquisition was
accounted for by the purchase method of accounting, with the purchase price to
be allocated to the fair value of assets acquired and liabilities assumed,
principally goodwill ($143.1 million). This goodwill will be amortized over its
estimated useful life of 20 years. The allocation of the purchase price is
tentative pending management's completion of the valuation of the purchased
assets and liabilities. However, management does not expect the final allocation
of the purchase price to differ significantly from the preliminary allocations.
 
     On April 30, 1998, the Company completed the acquisition of privately held
National Telecommunications of Florida, Inc. and NTC, Inc. (collectively,
"National"), an emerging switch-based competitive local exchange carrier and
established interexchange carrier. The operating results of National are
included in the Company's consolidated financial statements commencing on April
1, 1998. Aggregate consideration for the acquisition was approximately $59.5
million in cash, plus 2,909,796 shares of the Company's Common Stock, valued at
approximately $88.7 million, the retirement of $2.8 million in National's
long-term debt, and $2.2 million in acquisition related costs. The acquisition
was accounted for by the purchase method of accounting, with the purchase price
allocated to the fair value of assets acquired and liabilities assumed,
principally goodwill ($146.7 million). This goodwill will be amortized over its
estimated useful life of 20 years. The allocation of the purchase price is
tentative pending management's completion of the valuation of the purchased
assets and liabilities. However, management does not expect the final allocation
of the purchase price to differ significantly from the preliminary allocations.
 
     The 20 year amortization period assigned to the goodwill arising from the
Company's acquisitions of Shared, LDS and National is based on the Company's
analysis of their businesses. The Company considered the general stability of
these companies (i.e. the length of time that these three entities have already
successfully conducted business operations) particularly during periods of
increasing competition and technological developments. These companies have been
in operations approximately 13, 8 and 16 years, respectively. The Company also
considered the nature of their principal products and the anticipated effects of
changes in future business demand for their services, due to, among other
things, technological change and competition. The products and services offered
by these entities are mature and have a long life expectancy. The Company
believes the useful life of the associated goodwill will not be adversely
affected by future competition and technological developments and that a life of
20 years is appropriate. On the other hand, DIGEX, Incorporated ("DIGEX"), which
was acquired by the Company in 1997, operates in an emerging

                                        9
<PAGE>   10
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
Internet based marketplace and its predominant product offerings have been
developed principally in the last 3-4 years and are subject to more rapid
change. Consequently, a 10 year life was assigned to the goodwill arising from
the acquisition of DIGEX.
 
     The following unaudited pro forma results of operations present the
consolidated results of operations as if the acquisitions of DIGEX, Shared, LDS,
and National had occurred at the beginning of the respective periods. These pro
forma results do not purport to be indicative of the results that actually would
have occurred if the acquisition had been made as of that date or of results
which may occur in the future.
 
<TABLE>
<CAPTION>
                                                                  NINE MONTHS ENDED
                                                                    SEPTEMBER 30,
                                                              -------------------------
                                                                 1998          1997
                                                              -----------   -----------
                                                              (IN THOUSANDS, EXCEPT PER
                                                                     SHARE DATA)
<S>                                                           <C>           <C>
Revenue.....................................................   $ 567,302     $ 458,169
Net loss....................................................    (361,088)     (210,436)
Net loss attributable to common stockholders................    (429,206)     (241,243)
Basic and diluted net loss per common share.................       (9.54)        (5.86)
</TABLE>
 
NOTE 4.  BUSINESS RESTRUCTURING AND INTEGRATION PROGRAM
 
     During the second quarter of 1998, management committed to and commenced
implementation of the restructuring program (the "Program") which was designed
to streamline and refocus the Company's operations and facilitate the
transformation of the Company's five separate operating companies into one
Integrated Communications Provider ("ICP"). The significant activities included
in the Program include (i) consolidation, rationalization and integration of
network facilities, collocations, network management and network facility
procurement; (ii) consolidation and integration of the sales forces of the
Company and its recent acquisitions, including the integration of the Company's
products and services and the elimination of redundant headcount and related
costs; (iii) centralization of accounting and financial functions, including the
elimination of redundant headcount and related costs; (iv) development and
integration of information systems including the integration of multiple billing
systems and the introduction and deployment of automated sales force and
workflow management tools; (v) consolidation of office space and the elimination
of unnecessary legal entities; and (vi) exiting non-strategic businesses
including the elimination of headcount and related costs. The anticipated
completion date of the Program is December 31, 1999. The ultimate effect of the
Program is currently estimated by management to result in approximately $15.0
million of savings in operating costs per quarter. These savings will commence
as various Program activities are completed.
 
                                       10
<PAGE>   11
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
     The following table sets forth the significant components and activity in
the restructuring program reserve for the nine months ended September 30, 1998
(in millions):
 
<TABLE>
<CAPTION>
                                                                                     OTHER
                                       EMPLOYEE                                    BUSINESS
                                      TERMINATION      CONTRACT        ASSET      INTEGRATION
ACTIVITY                             BENEFITS(VII)   TERMINATIONS   IMPAIRMENTS      COSTS      TOTAL
--------                             -------------   ------------   -----------   -----------   -----
<S>                                  <C>             <C>            <C>           <C>           <C>
Network integration(i).............                     $ 0.9                                   $ 0.9
Sales force consolidation and
  branding(ii).....................      $0.4                                                     0.4
Consolidation of financial
  functions(iii)...................       0.9                                                     0.9
Information systems
  integration(iv)..................       0.7                                                     0.7
Campus consolidation(v)............                       2.3                                     2.3
  Exiting non-core
     businesses(vi)................       0.6            11.5           13.4          1.6        27.1
                                         ----           -----          -----         ----       -----
          Total provisions recorded
            during the quarter
            ended June 30, 1998....       2.6            14.7           13.4          1.6        32.3
Less: Payments and adjustments.....       0.9            10.1            9.2           --        20.2
                                         ----           -----          -----         ----       -----
Balance in accrual at September 30,
  1998.............................       1.7             4.6            4.2          1.6        12.1
                                         ====           =====          =====         ====       =====
</TABLE>
 
---------------
 
(i)  This activity consists primarily of the consolidation, rationalization and
     integration of network facilities, collocations, network management and
     network facility procurement. Contract terminations represent the estimated
     costs of terminating two contracts with MCI Communications Corporation.
(ii) This activity consists primarily of the consolidation and integration of
     the sales forces of the Company and its recent acquisitions, including the
     integration of the Company's products and services and the elimination of
     redundant headcount and related costs.
(iii)This activity consists of the centralization of accounting and financial
     functions, including the reduction of redundant headcount and related
     costs.
(iv) This activity consists of the development and integration of information
     systems, including the integration of multiple billing systems, and the
     introduction and deployment of automated sales force and workflow
     management tools. The only costs included in this category in the table
     above relate to the termination of certain employees as described in (vii)
     below.
(v)  This activity relates to the consolidation of office space. Contract
     termination costs represent the estimated costs of lease terminations for
     property exited as part of the Program.
(vi) This activity consists of the exiting of non-strategic businesses including
     the elimination of redundant headcount and related costs. Contract
     termination costs include the estimated cost to cancel a switched services
     contract with WorldCom, Inc. ("WorldCom") ($10.1 million) and lease
     termination payments. On September 30, 1998, the Company amended its
     agreement with WorldCom to provide the Company with an option for an
     earlier termination date and lower monthly minimum usage amounts. On
     October 27, 1998, the Company exercised its option, and, in connection
     therewith, paid $3.3 million to WorldCom. As a result, restructuring
     charges were reduced by $10.1 million during the third quarter of 1998. The
     option payment of $3.3 million was recorded in October 1998 as a deferred
     charge and will be amortized into operations over the remaining period of
     the contract. All wholesale long-distance contracts were terminated at
     various dates during 1998. Asset impairments relate to $9.2 million of
     accounts receivable balances from four customers that were reserved as a
     result of the Company's exit of the wholesale long-distance business. A
     majority of the accounts receivable associated with the wholesale long
     distance business arose during the first five months of 1998. As of March
     31, 1998, the Company believed that those amounts were collectible.
     Following the Company's May 1998 announcement that it intended to exit the
     wholesale long distance business, one of the customers in that business
     brought a lawsuit against the Company for breach of contract. At that time,
     the Company reassessed the collectibility of all accounts receivable
     remaining from customers in the exited business in light of the stated
     refusal of the customers to pay and the pending lawsuit, and reserved 100%
     of those amounts. The
 
                                       11
<PAGE>   12
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
     Company began to pursue its legal remedies, commencing with a countersuit,
     to collect a portion of the balances. No facts and circumstances have
     changed which would lead management to believe that a portion of the
     balances will ultimately be collectible; rather, the indications are that
     the outcome originally estimated will be experienced. If and when a final
     determination is made to forgo any further collection activities or pursuit
     of its legal remedies, the accounts will be written off. However, no such
     determination has been made to date. In addition, this category also
     includes $2.8 million related to equipment write-downs. The impaired assets
     consist of terminal servers with an estimated fair value of $0.4 million as
     of June 30, 1998. The fair value estimate was based on the Company's review
     of the historical operations and cash flows of the related Internet
     business that such assets support. The impairment loss of $2.8 million was
     recognized in connection with the Company's decision to outsource these
     services and to dispose of these assets. The remaining life of the assets
     of six months correlates to the time required to migrate the business to
     the third party provider. The revenue generated from the operations that
     the Company has exited amounted to $4.7 million and $2.8 million for the
     quarters ended June 30, 1998, and September 30, 1998, respectively.
(vii)The total number of employees affected by the restructuring program was
     280. The terminated employees were notified that their termination was
     involuntary, and of their associated benefit arrangements, prior to the
     date of the financial statements.
     Payments and other adjustments were comprised of the following (in
millions):
 
<TABLE>
<CAPTION>
DESCRIPTION                                                   AMOUNT
-----------                                                   ------
<S>                                                           <C>
Adjustment for contract termination.........................  $10.1
Cash payments related to severance..........................    0.9
Allowance for doubtful accounts receivable related to exit
  of wholesale long-distance business.......................    9.2
                                                              -----
                                                              $20.2
                                                              =====
</TABLE>
 
     As provided for in the Program, the Company also expensed other business
restructuring and integration costs that were incurred in the third quarter.
These costs represent incremental, redundant, or convergence costs that resulted
directly from implementation of the Program, but are required to be expensed as
incurred.
 
                                       12
<PAGE>   13
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
     The following table summarizes total Program costs and sets forth the
components of the other business restructuring and integration costs that were
expensed as incurred during the three and nine months ended September 30, 1998
(in millions):
 
<TABLE>
<CAPTION>
                                                         THREE MONTHS        NINE MONTHS
                                                             ENDED              ENDED
                                                         SEPTEMBER 30,      SEPTEMBER 30,
                                                             1998               1998
                                                        ---------------    ---------------
<S>                                                     <C>                <C>
Business restructuring charges
  Employee termination benefits(A)....................      $   --             $  2.6
  Contract terminations(A)............................          --               14.7
Other charges
  Asset impairments(A)................................          --               13.4
  Legal costs(A)......................................          --                1.6
Integration costs
  Network integration(B)..............................         8.8               21.2
  Facilities integration(C)...........................         0.1                0.2
  Department and employee realignment(D)..............         0.9                1.6
  Functional re-engineering(E)........................         0.5                1.2
  Year 2000(F)........................................         0.2                0.3
  Other(G)............................................         1.4                5.2
                                                            ------             ------
                                                              11.9               62.0
Changes in estimate
WorldCom contract negotiation.........................       (10.1)             (10.1)
                                                            ------             ------
     Total............................................      $  1.8             $ 51.9
                                                            ======             ======
</TABLE>
 
---------------
 
(A)  See prior table for components of cost.
 
(B)  Consists primarily of redundant network expense, with some employee salary
     costs of severed employees through their severance date.
(C)  Consists of rent expense for redundant facilities.
(D)  Consists of branding, training and relocation expenses.
(E)  Consists of consultant costs and some employee salary costs.
(F)  Consists of consultant costs.
(G)  Consists of losses on divested businesses, employee salary costs, legal,
     accounting and consulting costs.
 
NOTE 5.  LONG-TERM DEBT
 
     In January 1998, the over-allotment option with respect to the December
1997 issuance of the Company's 8.5% Senior Notes due 2008 (the "8.5% Senior
Notes") was exercised and the Company sold an additional $50.0 million principal
amount of 8.5% Senior Notes. Net proceeds to the Company amounted to
approximately $48.4 million.
 
     On May 27, 1998, the Company sold $450 million principal amount of 8.6%
Senior Notes due 2008 (the "8.6% Senior Notes") in a private placement
transaction. Subsequent thereto, the over-allotment option with respect to the
8.6% Senior Notes was exercised and the Company sold an additional $50.0 million
principal amount. Net proceeds to the Company, including the over-allotment,
amounted to approximately $488.0 million. Cash interest on the 8.6% Senior Notes
is payable semi-annually in arrears on June 1 and December 1 of each year,
commencing December 1, 1998. The 8.6% Senior Notes are redeemable at the option
of the Company at any time prior to June 1, 2003, in whole or in part, at the
Make-Whole Price (the greater of the sum of the principal amount plus the
present value of the principal, premium, and interest with respect to the
 
                                       13
<PAGE>   14
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
8.6% Senior Notes as of June 1, 2003, and the redemption price of the 8.6%
Senior Notes on June 1, 2003), plus accrued and unpaid interest and Liquidated
Damages (as defined in the indenture setting forth the terms of the 8.6% Senior
Notes), if any, thereon to the redemption date. On or after June 1, 2003, the
8.6% Senior Notes are subject to redemption by the Company, at rates commencing
at 104.3%, declining to 100% on June 1, 2006. In addition, at the option of the
Company, up to 25% of the aggregate principal amount of the 8.6% Senior Notes
originally issued may be redeemed at any time prior to June 1, 2001 at a
redemption price of 108.6% of the principal amount thereof plus accrued and
unpaid interest and Liquidation Damages, if any, thereon to the date of
redemption, with the net proceeds of one or more Qualified Equity Offerings (as
defined in the indenture setting forth the terms of the 8.6% Senior Notes);
provided, however that at least 75% in aggregate principal remains outstanding
following any such redemption and, provided further, that such redemption occurs
within 90 days of the date of the closing of such offering.
 
NOTE 6.  CAPITAL LEASE OBLIGATIONS
 
     As disclosed in the Company's Annual Report on Form 10-K as amended for the
year ended December 31, 1997, the Company is party to various capital lease
agreements for fiber optic cable, underground conduit equipment and utility
poles which extend through the year 2015.
 
     In March 1998, the Company and Williams Communications, Inc. ("Williams")
executed a Capacity Purchase Agreement which provides the Company with the right
to purchase transmission capacity on a non-cancelable indefeasible right of use
basis on the Williams fiber network for the next 20 years. The agreement covers
approximately 14,000 route miles of network facilities. The capitalized asset,
consisting of the Company's rights to use network facilities, including but not
limited to, fiber, optronics/electronics, digital encoders/decoders, telephone
lines and microwave facilities, in the amount of $417.0 million, is being
depreciated over the 20-year estimated useful life of the primary underlying
network asset, the fiber.
 
     Future minimum payments under the Williams capital lease at September 30,
1998, are as follows (in thousands):
 
<TABLE>
<S>                                                           <C>
Three months ending December 31, 1998.......................  $   5,883
Twelve months ending:
  1999......................................................     32,354
  2000......................................................     39,707
  2001......................................................     45,590
  2002......................................................     51,472
  2003......................................................     52,943
Thereafter..................................................    754,434
                                                              ---------
                                                                982,383
  Less amount representing interest.........................   (557,557)
                                                              ---------
  Present value of future minimum lease payments............  $ 424,826
                                                              =========
</TABLE>
 
     Certain executory costs, principally maintenance, associated with the
Williams agreement are being expensed as incurred.
 
NOTE 7.  PREFERRED STOCK
 
     On August 18, 1998, the Company sold 8,000,000 Depositary Shares (the
"Series F Depositary Shares") (aggregate liquidation preference $200 million)
each representing a one-hundredth interest in a share of the Company's 7% Series
F Junior Convertible Preferred Stock, (the "Series F Preferred Stock"), in a
private placement transaction. Net proceeds to the Company amounted to
approximately $193.8 million. Dividends on the Series F Preferred Stock
accumulate at a rate of 7% of the aggregate liquidation preference thereof and
 
                                       14
<PAGE>   15
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
are payable quarterly, in arrears. Dividends are payable in cash or, at the
Company's option, by issuance of shares of Common Stock of the Company. The
Series F Preferred Stock is convertible, subject to prior redemption, at any
time after November 16, 1998 at the option of the holder thereof into Common
Stock of the Company. The Series F Preferred Stock is redeemable, at the option
of the Company, in whole or part, at any time on or after October 17, 2001, at
rates commencing with 104%, declining to 100% on October 17, 2005.
 
     During July and August 1998, the Company exchanged (a) approximately 2.029
million shares of its Common Stock for approximately 1.487 million Depositary
Shares (each representing a 1/100th interest in a share of 7% Series D Junior
Convertible Preferred Stock (the "Series D Preferred Stock")) and (b)
approximately 1.423 million shares of its Common Stock for approximately 1.511
million Depositary Shares (each representing a 1/100th interest in a share of 7%
Series E Junior Convertible Preferred Stock ("the Series E Preferred Stock")),
pursuant to exchange agreements with certain holders of such Depositary Shares.
In connection with the conversion of shares, the Company recorded additional
preferred stock dividends of approximately $11.0 million during the third
quarter of 1998 representing the market value of the inducement feature of the
conversions.
 
NOTE 8.  COMPREHENSIVE INCOME
 
     In June 1997, the Financial Accounting Standards Board issued Statement of
Financial Accounting Standards No. 130, Reporting Comprehensive Income ("SFAS
130"). SFAS 130 requires that total comprehensive income be disclosed with equal
prominence as net income. Comprehensive Income is defined as changes in
stockholders' equity exclusive of transactions with owners such as capital
contributions and dividends. Adoption of SFAS 130, effective January 1, 1998,
had no impact on the Company as Comprehensive Income for the Company, as defined
by SFAS 130, equals net income for the three and nine months ended September 30,
1998.
 
                                       15
<PAGE>   16
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
NOTE 9.  EARNINGS PER SHARE
 
     The following table sets forth the computation of basic and diluted loss
per share of Common Stock (dollars in thousands, except shares and per share
amounts):
 
<TABLE>
<CAPTION>
                                         THREE MONTHS ENDED           NINE MONTHS ENDED
                                            SEPTEMBER 30,               SEPTEMBER 30,
                                      -------------------------   -------------------------
                                         1998          1997          1998          1997
                                      -----------   -----------   -----------   -----------
<S>                                   <C>           <C>           <C>           <C>
Numerator:
  Net loss..........................  $   (85,853)  $  (144,165)  $  (370,085)  $  (201,219)
  Preferred stock dividends and
     accretions.....................      (30,647)      (13,895)      (68,118)      (27,118)
                                      -----------   -----------   -----------   -----------
  Numerator for basic loss per
     share -- loss attributable to
     common stockholders............     (116,500)     (158,060)     (438,203)     (228,337)
  Effect of dilutive securities.....           --            --            --            --
                                      -----------   -----------   -----------   -----------
  Numerator for diluted loss per
     share -- income attributable to
     common stockholders after
     assumed conversions............  $  (116,500)  $  (158,060)  $  (438,203)  $  (228,337)
Denominator:
  Denominator for basic loss per
     share -- weighted-average
     shares.........................   47,041,191    33,479,460    41,948,399    32,925,462
  Effect of dilutive securities.....           --            --            --            --
                                      -----------   -----------   -----------   -----------
Denominator for diluted loss per
  share -- adjusted weighted-average
  shares............................   47,041,191    33,479,460    41,948,399    32,925,462
                                      ===========   ===========   ===========   ===========
Basic loss per share of Common
  Stock.............................  $     (2.48)  $     (4.72)  $    (10.45)  $     (6.93)
                                      ===========   ===========   ===========   ===========
Diluted loss per share of Common
  Stock.............................  $     (2.48)  $     (4.72)  $    (10.45)  $     (6.93)
                                      ===========   ===========   ===========   ===========
</TABLE>
 
     Unexercised options to purchase 6,484,148 and 6,640,814 shares of Common
Stock as of September 30, 1998 and 1997, respectively, and outstanding
convertible preferred stock, convertible into 17,079,495 shares of Common Stock
as of September 30, 1998, were not included in the computations of diluted loss
per share because assumed exercise/conversion would be anti-dilutive.
 
NOTE 10.  CONTINGENCIES
 
     On June 20, 1997, two purported class action complaints were filed in the
Court of Chancery of the State of Delaware in and for New Castle County
respectively by TAAM Associates, Inc. and David and Chaile Steinberg (the
"Complaints"), purported stockholders of DIGEX on behalf of all non-affiliated
common stockholders of DIGEX against Intermedia, DIGEX and the directors of
DIGEX (the "DIGEX Directors"). The Complaints allege that the DIGEX Directors
violated their fiduciary duties to the public stockholders of DIGEX by agreeing
to vote in favor of the merger between DIGEX and a wholly owned subsidiary of
Intermedia (the "Merger") and that Intermedia knowingly aided and abetted such
violation by offering to retain DIGEX management in their present positions and
consenting to stock option grants to certain executive officers of DIGEX. The
Complaints sought a preliminary and permanent injunction enjoining the Merger
but no applications were made for such injunctions prior to consummation of the
Merger on July 11, 1997. In addition, the Complaints seek cash damages from
DIGEX Directors. In August 1997, a motion to
 
                                       16
<PAGE>   17
                INTERMEDIA COMMUNICATIONS INC. AND SUBSIDIARIES
 
      NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS -- (CONTINUED)
 
dismiss the Complaints was filed on behalf of Intermedia, DIGEX, and the DIGEX
Directors. The action has been dormant since that time.
 
     These cases are in the early stages and no assurance can be given as to
their ultimate outcome. Intermedia, after consultation with its counsel,
believes that there are meritorious factual and legal defenses to the claims in
the Complaints. Intermedia intends to defend vigorously the claims in the
Complaints.
 
     The Company is not a party to any other pending legal proceedings except
for various claims and lawsuits arising in the normal course of business. The
Company does not believe that these normal course of business claims or lawsuits
will have a material effect on the Company's financial condition, results of
operations or cash flows.
 
     The Company maintains interconnection agreements with incumbent local
exchange carriers ("ILECs") in Florida, Georgia, and North Carolina. These
contracts govern the reciprocal amounts to be billed by competitive carriers for
terminating local traffic of Internet service providers ("ISPs") in each state.
During 1997, the Company recognized revenue from these ILECs of approximately
$10.0 million for these services. During the nine months ended September 30,
1998, the Company recognized an additional $22.4 million in revenue from these
services. Payments of approximately $2.2 million were received from the ILECs
during the third quarter of 1998.
 
     The Company accounts for reciprocal compensation with the ILECs, including
the activity associated with the disputed ISP traffic, as local traffic pursuant
to the terms of its interconnection agreements. Accordingly, revenue is
recognized in the period that the traffic is terminated. The circumstances
surrounding the disputes, including the status of cases that have arisen by
reason of similar disputes referred to below, is considered by management
periodically in determining whether reserves against unpaid balances are
warranted. As of September 30, 1998, provisions have not been considered
necessary by management.
 
     Management believes the issue related to mutual compensation for Internet
traffic to be an industry wide matter that will ultimately be resolved on a
state-by-state basis. To date, twenty-four state commissions have ruled on the
issue and found that ILECs must pay compensation to competitive carriers for
local calls to ISPs located on competitive carriers' networks. A number of other
state commissions currently have proceedings pending to consider this matter.
Management is pursuing this matter vigorously and believes the ILECs will
ultimately pay all amounts in full.
 
                                       17
<PAGE>   18
 
ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS
 
     The following discussion should be read in conjunction with the condensed
consolidated financial statements and notes thereto included herewith, and with
the Company's Management's Discussion and Analysis of Financial Condition and
Results of Operations and audited consolidated financial statements and notes
thereto included in the Company's Annual Report on Form 10-K as amended for the
year ended December 31, 1997 filed with the Commission.
 
OVERVIEW
 
     Intermedia has experienced continuous revenue growth since its inception in
1986. Since 1992, the Company has experienced an accelerated rate of revenue
growth. Building from its original base in Florida, Intermedia now provides
integrated telecommunications services nationally with a focus on customers who
have a substantial presence in the eastern United States. Through a combination
of internally generated growth and targeted acquisitions, the Company has
expanded its service territory and dramatically increased its customer base.
 
     Intermedia's customers include a broad range of business and government end
users and, to a lesser extent, ISPs and other carriers. The Company delivers
local network services, including local exchange service, primarily through
Company owned local and long distance switches and over a Company owned or
leased digital transport network.
 
     Often, leasing facilities enables the Company to more rapidly initiate
service to customers, reduces the risk of network construction or acquisition
and potentially improves cash flow due to the reduction or deferment of capital
expenditures. The Company offers enhanced data services to its customers on an
extensive inter-city network that connects its customers, either through its own
network or through other carriers, to locations throughout the country and
internationally. Through its 608 network to network interfaces ("NNIs") and 164
data switches, Intermedia has established one of the most densely deployed frame
relay switching network in the nation. The Company's nationwide interexchange
network, which it is upgrading to provide asynchronous transfer mode ("ATM")
capability, carries both its data network traffic and its voice network traffic.
 
     At its inception, Intermedia provided special access and private line
services to interexchange carriers ("IXCs"). In 1988, Intermedia was the first
telecommunications provider in Florida to begin providing special access and
private line services to business customers. In 1991, Intermedia began offering
specialized integration services such as construction of campus local area
networks ("LANs"), and in 1992, Intermedia introduced its first enhanced data
services based on frame relay technology, providing flexible capacity and highly
reliable end-to-end data service. The Company began offering interexchange long
distance service in December 1994, Internet services in 1995, local exchange
services in 1996 and integrated voice/data services via Single-T(SM) in 1997.
The pace with which the Company has introduced new service offerings has enabled
it to achieve substantial growth, expand its base of customers and diversify its
sources of revenue. The Company believes that business and government customers
will continue to account for a substantial share of its revenue because of
Intermedia's ability to offer such customers integrated, cost-effective
telecommunications solutions. The Company believes that during the first few
years of local exchange competition, some IXCs may enter the local exchange
market by becoming resellers of the Company's local services. If the IXCs pursue
a resale strategy, the amount of revenue the Company realizes from carriers may
increase during this period, although the Company does not depend on these IXC
resale revenues to satisfy its business plan.
 
     Network operating costs, administration and maintenance of facilities,
depreciation of network capital expenditures and sales, general and
administrative costs will continue to represent a large portion of the Company's
expenses for the next several years. In addition, the Company is experiencing
rapid growth in marketing and selling expenses consistent with the addition of
new customers and an increased level of selling and marketing activity. The
Company anticipates that as its customer base grows, incremental revenues will
be greater than incremental operating expenses.
 
                                       18
<PAGE>   19



 
     All of the marketing and selling expenses associated with the acquisition
of new customers are expensed as they are incurred even though these customers
are expected to generate recurring revenue for the Company for several years.
The continued expansion of the Company's networks in preparation for new
customers and the marketing of services to new and existing customers is
therefore adversely impacting EBITDA before certain charges of the Company in
the near term. From 1992 through 1995, the Company achieved positive EBITDA
before certain charges and increased its revenue base substantially. As a result
of significant investments in the resources necessary to launch local exchange
services and expand enhanced data services, the Company's EBITDA before certain
charges was negative for 1996 and 1997. The Company expects EBITDA before
certain charges to be positive for the full year of 1998. EBITDA before certain
charges consists of earnings (loss) before extraordinary loss on early
extinguishment of debt, interest expense, interest and other income, income
taxes, depreciation, amortization, charges for in-process R&D, and business
integration, restructuring and other costs associated with the Program. EBITDA
before certain charges does not represent funds available for management's
discretionary use and is not intended to represent cash flow from operations.
EBITDA before certain charges should not be considered as an alternative to net
loss as an indicator of the Company's operating performance or to cash flows as
a measure of liquidity. In addition, EBITDA before certain charges is not a term
defined by generally accepted accounting principals and as a result the EBITDA
before certain charges presented herein may not be comparable to similarly
titled measures used by other companies. The Company believes that EBITDA before
certain charges is often reported and widely used by analysts, investors and
other interested parties in the telecommunications industry. Accordingly, this
information has been disclosed herein to permit a more complete comparative
analysis of the Company's operating performance relative to other companies in
the industry.
 
     In January 1998, the over-allotment option with respect to the Company's
8.5% Senior Notes (December 23, 1997 issuance) was exercised and the Company
sold an additional $50.0 million principal amount of 8.5% Senior Notes. Net
proceeds to the Company amounted to approximately $48.4 million.
 
     On January 29, 1998, the Company announced a definitive multi-year
agreement to become a U S West Communications' ("US West") interLATA data
services provider. Under the terms of this agreement, the Company granted US
West a license to utilize and market the Company's portfolio of enhanced data
services.
 
     On March 10, 1998, the Company completed its acquisition of Shared, a
shared tenant communications services provider. Aggregate cash consideration for
the acquisition was approximately $782.2 million, including $62.3 million of
transaction expenses and fees relating to certain agreements, with the final
payment made March 10, 1998, and funded with the Company's existing cash
reserves in March 1998. The operating results of Shared are included in the
Company's consolidated financial statements commencing on January 1, 1998.
 
     On March 31, 1998, the Company acquired LDS, a regional interexchange
carrier. Aggregate consideration for the acquisition was approximately $15.7
million in cash, plus 5,359,748 shares of the Company's Common Stock, valued at
approximately $137.2 million, the retirement of $15.1 million in LDS's long-term
debt, and acquisition related expenses of $2.4 million. The cash portion of the
acquisition was funded with the Company's existing cash reserves in March 1998.
The operating results of LDS for the one day of ownership during the first
quarter of 1998 are considered immaterial. The operating results of LDS are
included in the Company's consolidated financial statements commencing on April
1, 1998.
 
     In March 1998, the Company and Williams executed a Capacity Purchase
Agreement which provides the Company with the right to purchase transmission
capacity on a non-cancelable indefeasible right of use basis on the Williams
fiber network for the next 20 years. The agreement covers approximately 14,000
route miles.
 
     On April 29, 1998, the Company announced that it had committed resources to
the Program, a plan to implement the integration of acquired businesses to
maximize the synergies that will be realized and to reduce future costs. During
the second quarter of 1998, the Company developed and began implementation of
the Program which was designed to streamline and refocus the Company's
operations and transform Intermedia's five separate operating companies into one
ICP. The significant activities included in the Program include (i)
consolidation, rationalization and integration of network facilities,
collocations, network management and

                                       19
<PAGE>   20
 
network facility procurement; (ii) consolidation and integration of the sales
forces of the Company and its recent acquisitions, including the integration of
the Company's products and services and the elimination of redundant headcount
and related costs; (iii) centralization of accounting and financial functions,
including the elimination of redundant headcount and related costs; (iv)
development and integration of information systems including the integration of
multiple billing systems and the introduction and deployment of automated sales
force and workflow management tools; (v) consolidation of office space and the
elimination of unnecessary legal entities; and (vi) exiting non-strategic
businesses including the elimination of headcount and related costs. The
anticipated completion date of the Program is December 31, 1999. The ultimate
effect of the Program is currently estimate by management to result in
approximately $15.0 million of savings in operating costs per quarter. These
savings will commence as various Program activities are completed.
 
     In connection with the adoption of the Program, the Company recorded a
restructuring charge during the second quarter of approximately $32.3 million.
The Company also expensed during the second and third quarter of 1998 other
business restructuring and integration costs associated with the Program in the
amounts of $17.8 million and $1.8 million, respectively. Management anticipates
that all activities included in the Program will be completed by the end of
1999, and the Company anticipates incurring additional related business
integration and restructuring costs through the end of that period, which will
be excluded from the calculation of EBITDA before certain charges.
 
     On April 30, 1998, the Company completed the acquisition of privately held
National, an emerging switch-based competitive local exchange carrier and
established interexchange carrier. Aggregate consideration for the acquisition
was approximately $59.5 million in cash, plus 2,909,796 shares of the Company's
Common Stock, valued at approximately $88.7 million, the retirement of $2.8
million in National's long-term debt, and $2.2 million in acquisition related
costs. The cash portion of the acquisition was funded with the Company's
existing cash reserves in April 1998. The operating results of National are
included in the Company's consolidated financial statements commencing on April
1, 1998.
 
     On May 19, 1998, the Company entered into an agreement with Ameritech
Communications International ("Ameritech") for the mutual provisioning of
national data services.
 
     On May 27, 1998, the Company sold $450.0 million principal amount of its
8.6% Senior Notes in a private placement transaction. Subsequently, the
over-allotment option with respect to the 8.6% Senior Notes was exercised and
the Company sold an additional $50.0 million principal amount of 8.6% Senior
Notes. Net proceeds to the Company, including the proceeds from the exercise of
the over-allotment, amounted to approximately $488.0 million.
 
     Cash interest on the 8.6% Senior Notes is payable semi-annually in arrears
on June 1 and December 1 of each year, commencing December 1, 1998. The 8.6%
Senior Notes are redeemable at the option of the Company at any time prior to
June 1, 2003, in whole or in part, at the Make-Whole Price (the greater of the
sum of the principal amount plus the present value of the principal, premium,
and interest with respect to 8.6% Senior Notes as of June 1, 2003, and the
redemption price of 8.6% Senior Notes on June 1, 2003), plus accrued and unpaid
interest and Liquidated Damages, if any, thereon to the redemption date. On or
after June 1, 2003, the 8.6% Senior Notes are subject to redemption by the
Company, at rates commencing at 104.3%, declining to 100% on June 1, 2006. In
addition, at the option of the Company, up to 25% of the aggregate principal
amount of the 8.6% Senior Notes originally issued may be redeemed at any time
prior to June 1, 2001 at a redemption price of 108.6% of the principal amount
thereof plus accrued and unpaid interest and Liquidation Damages, if any,
thereon to the date of redemption, with the net proceeds of one or more
Qualified Equity Offerings; provided, however that at least 75% in aggregate
principal remains outstanding following any such redemption and, provided
further, that such redemption occurs within 90 days of the date of the closing
of such offering.
 
     On August 18, 1998, the Company sold 8,000,000 Series F Depositary Shares
(aggregate liquidation preference $200 million) each representing a 1/100th
interest in a share of the Company's Series F Preferred Stock, in a private
placement transaction. Net proceeds to the Company amounted to approximately
$193.8 million. Dividends on the Series F Preferred Stock accumulate at a rate
of 7% of the aggregate liquidation preference thereof and are payable quarterly,
in arrears. Dividends are payable in cash or, at the Company's

                                       20
<PAGE>   21
 
option, by issuance of shares of Common Stock of the Company. The Series F
Preferred Stock is convertible, subject to prior redemption, at any time after
November 16, 1998 at the option of the holder thereof into Common Stock of the
Company. The Series F Preferred Stock is redeemable, at the option of the
Company, in whole or part, at any time on or after October 17, 2001, at rates
commencing with 104%, declining to 100% on October 17, 2005.
 
     On September 21, 1998, the Company entered into a multi-year agreement,
having multiple one-year extension options, with Bell Atlantic Corporation
("Bell Atlantic"). Under the terms of this agreement, Bell Atlantic will resell
Intermedia's high-speed and low-speed frame relay services under the Bell
Atlantic brand. The operational alignment between the two companies should
result in an integrated extension of Bell Atlantic's operations and service
delivery functions, all transparent to the customer, and Bell Atlantic will be
licensed to use the Company's advanced network monitoring system. Service under
this agreement will begin when and if Bell Atlantic gains approval to offer
long-distance services in its primary east coast markets under the
Telecommunications Act of 1996.
 
PLAN OF OPERATION
 
     For the remainder of 1998, the Company believes that its revenues will be
similar in amount to its revenues for the third quarter of 1998 which will
include revenue growth balanced between its enhanced data and local exchange
services. Based on the Company's analysis of Federal Communications Commission
data and its knowledge of the industry, the Company estimates that the market
for enhanced data, local exchange, and interexchange services was approximately
$34.0 billion in 1997 in the Company's service territory. As a result of the
Company's actual and planned expansion in 1998, including the acquisitions of
Shared, LDS and National, the Company expects to be positioned to provide these
services in markets with a total opportunity of more than $99.2 billion by the
end of 1998.
 
     In order to develop its business more rapidly and efficiently utilize its
capital resources, the Company plans to use the existing fiber optic
infrastructure of other providers in addition to using its own existing
networks. The Company believes transport provided on fiber optic systems has
become commodity-like, and its capital expenditures are better focused on
intelligent switching and other more strategic network components required to
implement a Packet/Cell Switched Network. While the Company will use significant
amounts of capital to deploy enhanced data and voice switches on a demand driven
basis in selected markets, Intermedia believes its substantial existing network
capacity should enable it to add new customers and provide additional services
that will result in increased revenues with lower incremental costs and,
correspondingly, improve its EBITDA before certain charges. For example, selling
additional services, such as local exchange services, to existing or new
customers allows the Company to utilize unused portions of the capacity inherent
in its existing fiber optic networks. This operating leverage increases the
utilization of the network with limited additional capital expenditures. The
Company's strategy to offer a full complement of telecommunications services is
designed to enable the Company to take advantage of the operating leverage of
its networks.
 
                                       21
<PAGE>   22
 
RESULTS OF OPERATIONS
 
     The following table presents, for the periods indicated, certain
information derived from the Unaudited Condensed Consolidated Statements of
Operations of the Company, expressed in percentages of revenue:
 
<TABLE>
<CAPTION>
                                                     THREE MONTHS        NINE MONTHS
                                                         ENDED              ENDED
                                                     SEPTEMBER 30,      SEPTEMBER 30,
                                                    ---------------    ---------------
                                                    1998      1997     1998      1997
                                                    -----    ------    -----    ------
<S>                                                 <C>      <C>       <C>      <C>
Revenues:
  Local network services..........................   22.8%     16.6%    22.3%     15.4%
  Enhanced data services..........................   24.7      43.3     24.4      33.2
  Interexchange services..........................   37.2      38.8     38.3      48.9
  Integration services............................   15.3       1.3     15.0       2.5
                                                    -----    ------    -----    ------
                                                    100.0     100.0    100.0     100.0
Expenses:
  Network operations..............................   43.5      68.8     46.9      70.4
  Facilities administration and maintenance.......    7.8      14.0      9.3      13.0
  Cost of goods sold..............................    9.9        .7      9.7       1.5
  Selling, general and administrative.............   30.9      35.1     31.2      39.3
  Depreciation and amortization...................   28.4      22.6     28.0      20.7
  Charge off of purchased in-process R&D..........     --      84.2     12.1      36.3
  Business restructuring and integration..........    0.9        --     10.0        --
                                                    -----    ------    -----    ------
Loss from operations..............................  (21.4)   (125.4)   (47.2)    (81.2)
Other income (expense):
  Interest expense................................  (28.0)    (24.8)   (29.1)    (24.1)
  Other income....................................    4.8       9.4      5.0      10.1
                                                    -----    ------    -----    ------
Net Loss before extraordinary item................  (44.6)   (140.8)   (71.3)    (95.2)
Extraordinary loss on early extinguishment of
  debt............................................     --     (61.5)      --     (26.5)
                                                    -----    ------    -----    ------
Net loss..........................................  (44.6)   (202.3)   (71.3)   (121.7)
  Preferred stock dividends and accretions........  (15.9)    (19.5)   (13.1)    (16.4)
                                                    =====    ======    =====    ======
Net loss attributable to common stockholders......  (60.6)%  (221.8)%  (84.4)%  (138.1)%
                                                    =====    ======    =====    ======
</TABLE>
 
     The following table sets forth other statistical data derived from the
Company's operating records:
 
<TABLE>
<CAPTION>
                                                       SEPTEMBER 30, 1998   SEPTEMBER 30, 1997
                                                       ------------------   ------------------
<S>                                                    <C>                  <C>
Local and Long Distance Services:(1)
  Buildings connected(2).............................           4,331                2,703
  Voice switches in operation........................              21                   13
  Long distance billable minutes(3)..................     516,897,223          111,049,341
  Access line equivalents............................         311,898               50,740
  Access line equivalents per local switch(4)........           7,303                3,494
Enhanced data services:(1)
  Data switches installed............................             164                  130
  Nodes in service(5)................................          30,266               17,286
  NNI connections....................................             608                  366
Employees............................................           3,678                1,820
</TABLE>
 
---------------
 
(1) Amounts reflected in the table are based upon information contained in the
    Company's operating records.
(2) Includes both on-net direct connections with Intermedia-owned fiber optic
    cable and on-net extended connections with leased circuits.
(3) Amount represents billable minutes for the three months ended September 30,
    1998 and 1997, respectively.
 
                                       22
<PAGE>   23
 
(4) Calculated by dividing the number of on-switch access line equivalents by
    the number of switches providing local service. Excludes access lines
    contributed by Shared.
(5) Amount represents an individual point of origination and termination of data
    served by the Company's enhanced network.
 
  Quarter Ended September 30, 1998 Compared to Quarter Ended September 30, 1997:
 
Revenue
 
     Total revenue increased 170.0% to $192.4 million for the third quarter of
1998 compared to $71.2 million for the same period in 1997. This increase was
principally the result of the acquisitions of Shared, LDS, and National. The
Company has also continued its efforts to introduce new services and increase
the focus of the Company's sales force on offering a full suite of
telecommunications services to an expanding market. While the Company's core
strategic revenue categories continue to grow, the Company expects total revenue
in the fourth quarter of 1998 to approximate the third quarter level and long
term revenue growth in the aggregate to resume in 1999. The Company plans to
maintain its emphasis on sales of key services such as enhanced data and local
service. The Company also expects continued demand created by customers in need
of Year 2000 upgrades, which is a catalyst for new systems purchases, and a
positive revenue impact as a result of the network partnership agreements.
 
     Local network services revenue increased 270.6% to $43.8 million for the
third quarter of 1998 compared to $11.8 million for the same period in 1997.
This increase was principally due to the acquisition of Shared during the first
quarter of 1998 and the acquisition of National during the second quarter of
1998, and the continued rollout of local exchange services into additional
markets. The number of access line equivalents has increased by 261,158 from
October 1, 1997 through the end of the third quarter of 1998. The Company was
certified as a comprehensive local exchance carrier ("CLEC") in 36 states and
the District of Columbia as of the end of the third quarter of 1998.
 
     Enhanced data services revenue increased 54.3% to $47.6 million for the
third quarter of 1998 compared to $30.8 million for the same period in 1997.
This increase was principally due to the acquisition of LDS during the first
quarter of 1998 and the expansion of the Company's enhanced data network. The
data network was expanded by 34 switches, 242 NNI connections, and 12,980 new
frame relay nodes. In addition, the Company experienced an increased amount of
sales in frame relay services and new web site installations during the nine
month period ended September 30, 1998.
 
     Interexchange services revenue increased 158.9% to $71.6 million for the
third quarter of 1998 compared to $27.6 million for the same period in 1997.
This increase resulted principally from the acquisitions of Shared and LDS
during the first quarter of 1998, the acquisition of National during the second
quarter of 1998, strong growth in long distance switched revenue, and steady
growth in interLATA transport. Interexchange revenues were negatively impacted
during the third quarter of 1998 as a result of the Company's decision to exit
the low margin wholesale international long distance segment. Long distance
billable minutes increased to 516.9 million for the third quarter of 1998
compared to 111.0 million for the same period in 1997.
 
     Integration services revenue increased 2,992.2% to $29.4 million for the
third quarter of 1998 compared to $1.0 million for the same period in 1997. This
increase was principally due to the acquisition of Shared during the first
quarter of 1998.
 
Operating Expenses
 
     Total operating expenses increased 45.4% to $233.6 million for the third
quarter of 1998 compared to $160.6 million for the same period in 1997. The
increase resulted principally from the acquisitions of Shared and LDS during the
first quarter of 1998 and the acquisition of National during the second quarter
of 1998. The Company has recorded approximately $1.8 million (net of a $9.1
million reduction in business restructuring costs associated with a contract
negotiation), in the third quarter of 1998 for the execution of the business
restructuring and integration program, has increased support costs relating to
the significant
 
                                       23
<PAGE>   24
 
expansion of the Company's owned and leased networks, and has continued
expansion in personnel to sustain and support the Company's growth.
 
     Network operations expenses increased 70.9% to $83.8 million for the third
quarter of 1998 compared to $49.0 million for the same period in 1997. The
increase resulted principally from the acquisitions of Shared and LDS in the
first quarter of 1998 and the acquisition of National in the second quarter of
1998. The Company has incurred increased expenses in leased network capacity
associated with the growth of local network service, enhanced data service, and
interexchange service revenues. The Williams agreement positively impacted
network operations expenses during 1998 by eliminating certain backbone network
costs that were previously accounted for as operating leases.
 
     Facilities administration and maintenance expenses increased 49.6% to $14.9
million for the third quarter of 1998 compared to $10.0 million for the same
period in 1997. The increase was principally due to the acquisitions of Shared
and LDS in the first quarter of 1998 and the acquisition of National in the
second quarter of 1998. The increase also resulted from support costs relating
to the expansion of the Company's owned and leased network capacity, increases
in maintenance expenses due to network expansion and increased payroll expenses
related to hiring additional engineering and operations staff to support and
service the expanding network, including the increase in volume relating to the
US West and Ameritech agreements. Facilities administration and maintenance
expenses were positively impacted by the Company's exit of the wholesale
interexchange business.
 
     Cost of goods sold increased 3680.1% to $19.0 million for the third quarter
of 1998 compared to $0.5 million for the same period in 1997. This increase was
principally due to the acquisition of Shared during the first quarter of 1998.
 
     Selling, general and administrative expenses increased 137.9% to $59.5
million for the third quarter of 1998 compared to $25.0 million for the same
period in 1997. The increase was principally due to the acquisitions of Shared
and LDS in the first quarter of 1998 and the acquisition of National in the
second quarter of 1998. The acquisitions of Shared, LDS, and National
contributed to the increase by approximately $10.3 million, $4.3 million, and
$2.4 million, respectively. The Company has experienced continued personnel
growth, represented by departmental expense increases in sales of approximately
$8.5 million, marketing of approximately $1.1 million, management information
services of approximately $1.9 million, and customer operations and circuit
design and provisioning of approximately $4.1 million. The growth in headcount
was directly related to the need to support the Company's data partnership
agreements.
 
     Depreciation and amortization expenses increased 239.0% to $54.6 million
for the third quarter of 1998 compared to $16.1 million for the same period in
1997. This increase was principally due to additions to telecommunications
equipment placed in service since October 1, 1997, relating to ongoing network
expansion, as well as, the acquisitions Shared, LDS, and National which
contributed, based on preliminary estimates, approximately $662.8 million,
$143.1 million, and $146.7 million of goodwill and acquired intangibles,
respectively. Additional depreciation charges of approximately $5.1 million
resulted from the long-term lease of capital assets from Williams, which began
during March of 1998. Depreciation and amortization expense is expected to
increase in future periods as the Company expands the network and depreciates
and amortizes intangibles associated with the businesses acquired. Previously
reported amortization expense has been restated as a result of the Company's
restatement of the charge for in-process R&D and restatement for the
reallocation of goodwill to identifiable intangible assets.
 
     Charge for in-process R&D of $60.0 million for the third quarter of 1997
represents the amount of purchased in-process R&D associated with the purchase
of DIGEX. This allocation represents the estimated fair value based on
risk-adjusted cash flows related to the incomplete projects. At the date of
acquisition, the development of these projects had not yet reached technological
feasibility and in-process R&D had no alternative future uses. Accordingly,
these costs were expensed as of the acquisition date and were recorded as a
one-time charge to earnings in the third quarter of 1997.
 
     In making its purchase price allocation, the Company relied on present
value calculations of income, an analysis of project accomplishments and
completion costs, an assessment of overall contribution, as well as
 
                                       24
<PAGE>   25
 
project risk. The amounts assigned to the in-process R&D were determined by
identifying significant research projects for which technological feasibility
had not been established. These included development, engineering, and testing
activities associated with specific and substantial network projects including
new router technology related to traffic management and very high speed data
streams, as well as value-added services such as multicasting and new advanced
web management capabilities.
 
     The value assigned to purchased in-process R&D was determined by estimating
the costs to develop the purchased in-process R&D into commercially viable
products and services, estimating the resulting net cash flows from the
projects, and discounting the net cash flows to their present value.
 
     Remaining development efforts for DIGEX projects include various phases of
design, development, and testing. Anticipated completion dates for the
in-process R&D projects are expected to occur by the end of 1998, after which
the Company expects to begin generating economic benefits from the technologies.
Expenditures to complete these projects are expected to total approximately $0.5
million in the fourth quarter of 1998.
 
     These estimates are subject to change, given the uncertainties of the
development process, and no assurance can be given that deviations from these
estimates will not occur. Management expects to continue development of these
efforts and believes the Company has a reasonable chance of successfully
completing the R&D programs. However, there is a risk associated with the
completion of the projects, and there is no assurance that any will meet with
either technological or commercial success. Failure to complete the in-process
R&D programs would result in the loss of the expected economic return inherent
in the fair value allocation.
 
     Business restructuring and integration expense of approximately $1.8
million was recorded by the Company during the third quarter of 1998, which
consists of costs related to businesses exited and integration and other
restructuring costs, net of a $9.1 million reduction in business restructuring
costs associated with a contract negotiation. Such costs were comprised
primarily of network integration, back office accounting integration,
information systems integration costs, and costs associated with positions
scheduled to be eliminated by the second quarter of 1999. These costs represent
incremental, redundant, or convergence costs that result directly from
implementation of the Program but are required to be expensed as incurred. Such
costs were substantially in line with the amounts expected for the third quarter
by management. Additional incremental, redundant and convergence costs within
this category of Program cost will be expensed as they are incurred each quarter
over the Program implementation period. Management currently expects these
additional costs to amount to approximately $33.2 million over the remainder of
the Program. Future cash outlays are expected for all components of the
remaining $12.1 million accrual (refer to Note 4), with the exception of
approximately $4.2 million for asset impairment write-downs, which are expected
to occur during the fourth quarter of 1998. The Company expects future cash
outlays of approximately $4.3 million during the fourth quarter of 1998, $1.9
million during 1999, and the Company expects approximately $1.7 million to occur
evenly throughout the Program.
 
     The Company's condensed consolidated financial statements for the three and
nine month periods ended September 30, 1998 have been restated to reflect a
reduction of this charge by $7.9 million and $10.1 million, respectively,
primarily as a result of a contract negotiation during the third quarter as
described herein and in Note 2 of the Notes to Condensed Consolidated Financial
Statements.
 
Interest Expense
 
     Interest expense increased 204.9% to $53.9 million for the third quarter of
1998 compared to $17.7 million for the same period in 1997. This increase
primarily resulted from interest expense on approximately $1.2 billion of senior
notes issued from October 1, 1997 through the end of the third quarter of 1998.
In addition, the Company recorded interest expense of $10.0 million during the
third quarter of 1998 related to the capital lease with Williams. Also included
in 1998 interest expense is $18.5 million of debt discount amortization and $1.3
million of deferred loan cost amortization, both of which are non-cash items.
Interest expense capitalized in connection with the Company's construction of
telecommunications equipment
 
                                       25
<PAGE>   26
 
amounted to approximately $1.8 million and $1.0 million for the three months
ended September 30, 1998 and 1997, respectively.
 
Other Income
 
     Other income increased 38.2% to $9.3 million for the third quarter of 1998
compared to $6.7 million for the same period in 1997. This increase was
primarily the result of interest earned on the cash available from the proceeds
of the issuance of securities in 1997, the exercise of the over-allotment option
with respect to the 8.5% Senior Notes in January 1998, the issuance of the 8.6%
Senior Notes in May 1998, and the issuance of the Series F Preferred Stock in
August 1998.
 
Extraordinary Loss
 
     The extraordinary loss of $43.8 million recorded during the third quarter
of 1997 consisted of pre-payment penalties relating to certain indebtedness
which was repaid from the proceeds of the offering of the 11 1/4% Senior Notes
due 2007 issued in July 1997 and the write-off of the unamortized deferred
financing costs associated with the indebtedness repaid.
 
Net Loss
 
     Net loss decreased 40.4% to $85.9 million for the third quarter of 1998
compared to $144.2 million for the same period in 1997. The decrease resulted
principally from the acquisitions of Shared and LDS in the first quarter of 1998
and National in the second quarter of 1998. In addition, the Company has
realized improved operating margins as a result of the restructuring and
integration program, improved product strategy, and reduced network costs due to
the network partnership agreements. The Company's "on-switch" sales strategy has
also contributed to the improved overall margins.
 
Preferred Stock Dividends and Accretions
 
     Preferred stock dividends and accretions increased 120.6% to $30.6 million
for the third quarter of 1998 compared to $13.9 million for the same period in
1997. The increase was due to the issuance of the two series of preferred stock,
in October 1997 and August 1998, and the conversion of approximately 15,000
shares of the Company's Series D Preferred Stock and approximately 15,000 shares
of the Company's Series E Preferred Stock into Common Stock. The Company
recorded a charge of approximately $11.0 million during the third quarter of
1998 representing the market value of the inducement feature of the conversions.
In addition, preferred stock dividends were paid in the form of Common Stock and
preferred stock. Management does not expect to pay cash dividends in the
foreseeable future.
 
EBITDA Before Certain Charges
 
     EBITDA before certain charges increased 214.1% to $15.1 million for the
third quarter of 1998 compared to $(13.3) million for the same period in 1997.
The increase was principally the result of the acquisitions of Shared and LDS in
the first quarter of 1998 and the acquisition of National in the second quarter
of 1998. These acquisitions contributed to improved EBITDA before certain
charges primarily by consolidating sales forces and introducing the Company's
products into additional markets. The Company has continued its efforts to
consolidate traffic through the Williams backbone network, as well as, through
the Company's existing networks in an efficient manner. In addition, the Company
has been successful in selling more of its access lines "on switch" and
increasing its mix of higher margin products. The business restructuring and
integration program has yielded benefits by eliminating redundant costs
associated with rationalizing and integrating the recent acquisitions. In
addition, the Company has reduced network operation expenses, facilities
administration and maintenance expenses, and selling, general and administrative
expenses as a percentage of revenue in the third quarter of 1998 as compared to
the same period in 1997.
 
                                       26
<PAGE>   27
 
  Nine Months Ended September 30, 1998 Compared to Nine Months Ended September
30, 1997:
 
Revenue
 
     Total revenue increased 214.2% to $519.4 million for the nine months ended
September 30, 1998 compared to $165.3 million for the same period in 1997. The
increase was principally the result of the acquisitions of Shared and LDS in the
first quarter of 1998, the acquisition of National in the second quarter of
1998, the introduction of new services, and the increased focus of the Company's
sales force on offering a full suite of telecommunications services to an
expanding market. The Company expects revenue in the fourth quarter of 1998 to
approximate the third quarter level and long term revenue growth to resume in
1999. The Company plans to maintain its emphasis on sales of key services such
as enhanced data and local service. The Company also expects continued demand
created by customers in need of Year 2000 upgrades, which is a catalyst for new
systems purchases, and a positive revenue impact as a result of the network
partnership agreements. In addition, the Company is continuing its integration
of the recent acquisitions and further development of cross-selling programs.
 
     Local network services revenue increased 354.3% to $115.6 million for the
nine months ended September 30, 1998 compared to $25.5 million for the same
period in 1997. This increase was principally due to the acquisition of Shared
during the first quarter of 1998, the acquisition of National during the second
quarter of 1998, and the increased number of local customers over the same
period in 1997. The number of access line equivalents increased by 261,158 from
October 1, 1997 through the end of the third quarter of 1998. Additionally, the
Company successfully continued its rollout of local exchange services into
additional markets. The Company was certified as a CLEC in 36 states and the
District of Columbia as of the end of the third quarter of 1998.
 
     Enhanced data services revenue increased 131.2% to $126.8 million for the
nine months ended September 30, 1998 compared to $54.8 million for the same
period in 1997. This increase resulted principally from the inclusion of three
full quarters of enhanced data services revenues in 1998 relating to the
acquisition of DIGEX compared to one quarter during the same period in 1997. In
addition, the increase was attributable to the acquisition of LDS, effective
April 1, 1998, and the expansion of the Company's enhanced data network by 34
switches, 242 NNI connections, and 12,980 new frame relay nodes from October 1,
1997 through the end of the third quarter of 1998.
 
     Interexchange services revenue increased 146.1% to $199.0 million for the
nine months ended September 30, 1998 compared to $80.9 million for the same
period in 1997. This increase resulted principally from the acquisitions of
Shared and LDS in the first quarter of 1998, and the acquisition of National in
the second quarter of 1998. The Company has experienced strong growth in long
distance switched revenue and steady growth in interLATA transport.
Interexchange revenues were negatively impacted during the third quarter of 1998
by the Company's decision to exit the low margin wholesale long distance
segment. Long distance billable minutes increased to 1,252.3 million for the
first nine months of 1998 compared to 300.0 million for the same period in 1997.
 
     Integration services revenue increased 1,775.8% to $77.9 million for the
nine months ended September 30, 1998 compared to $4.2 million for the same
period in 1997. This increase resulted primarily from the acquisition of Shared
during the first quarter 1998, as well as, the Company's continued focus on
providing a total service package to its customers.
 
Operating Expenses
 
     Total operating expenses increased 155.2% to $764.4 million for the nine
months ended September 30, 1998 compared to $299.5 million for the same period
in 1997. The increase resulted principally from the acquisitions of Shared and
LDS in the first quarter of 1998 and the acquisition of National in the second
quarter of 1998. The Company has recorded a one-time charge to earnings of $63.0
million during the first quarter of 1998 for purchased in-process R&D associated
with the acquisition of Shared compared to a similar charge relating to the
acquisition of DIGEX in the prior period of $60.0 million. Additionally, the
Company recorded expenses of approximately $51.9 million in connection with the
execution of the Program during the
 
                                       27
<PAGE>   28
 
first nine months of 1998, increased support costs relating to the significant
expansion of the Company's owned and leased networks, and has continued
expanding its personnel to sustain and support the Company's growth.
 
     Network operations expenses increased 109.2% to $243.3 million for the nine
months ended September 30, 1998 compared to $116.3 million for the same period
in 1998. The increase resulted principally from the acquisitions of Shared and
LDS in the first quarter of 1998, and the acquisition of National in the second
quarter of 1998. The Company has incurred increased expenses in leased network
capacity associated with the growth of local network service, enhanced data
service, and interexchange service revenues. The Williams agreement positively
impacted network operations expenses during 1998 by eliminating certain backbone
network costs that were previously accounted for as operating leases.
 
     Facilities administration and maintenance expenses increased 126.6% to
$48.5 million for the nine months ended September 30, 1998 compared to $21.4
million for the same period in 1997. The increase was principally the result of
the acquisitions of Shared and LDS in the first quarter of 1998 and the
acquisition of National in the second quarter of 1998. The increase also
resulted from support costs relating to the expansion of the Company's owned and
leased network capacity, increases in maintenance expense due to network
expansion, and increased payroll expenses related to hiring additional
engineering and operations staff to support and service the expanding network,
including the increase in volume relating to the US West and Ameritech
agreements. Facilities administration and maintenance expenses were positively
impacted by the Company's exit of the wholesale interexchange business.
 
     Cost of goods sold increased 1,867.8% to $49.9 million for the nine months
ended September 30, 1998 compared to $2.5 million for the same period in 1997.
This increase was principally due to the acquisition of Shared during the first
quarter of 1998.
 
     Selling, general and administrative expenses increased 149.7% to $162.2
million for the nine months ended September 30, 1998 compared to $65.0 million
for the same period in 1997. The increase was principally due to the
acquisitions of Shared and LDS in the first quarter of 1998, and the acquisition
of National in the second quarter of 1998. The acquisitions of Shared, LDS, and
National contributed to the increase by approximately $27.2 million, $9.1
million, and $5.2 million, respectively. The Company has experienced continued
personnel growth, represented by departmental expense increases in sales of
approximately $24.5 million, marketing of approximately $3.1 million, management
information services of approximately $4.7 million, and customer operations and
circuit design and provisioning of approximately $11.1 million. The growth in
headcount was directly related to the need to support the Company's data network
partnership agreements.
 
     Depreciation and amortization expenses increased 324.7% to $145.6 million
for the nine months ended September 30, 1998 compared to $34.3 million for the
same period in 1997. This increase was principally due to additions of
telecommunications equipment placed in service since October 1, 1997, relating
to ongoing network expansion, as well as, the acquisitions Shared, LDS, and
National which contributed, based on preliminary estimates, approximately $662.8
million, $143.1 million, and $146.7 million of goodwill and acquired
intangibles, respectively. Additional depreciation charges of approximately
$15.4 million resulted from the long-term lease of capital assets from Williams
in March 1998. Depreciation and amortization expense is expected to increase in
future periods as the Company expands the network and depreciates and amortizes
intangibles associated with the businesses acquired. Previously reported
amortization expense has been restated as a result of the Company's restatement
of the charge for in-process R&D and restatement for the reallocation of
goodwill to identifiable intangible assets discussed below.
 
     Charge for in-process Research & Development of $63.0 million for the first
nine months of 1998 represents the amount of purchased in-process R&D associated
with the purchase of Shared. This allocation represents the estimated fair value
based on risk-adjusted cash flows related to the incomplete projects. At the
date of acquisition, the development of these projects had not yet reached
technological feasibility and in-process R&D had no alternative future uses.
Accordingly, these costs were expensed as of the acquisition date and were
recorded as a one-time charge to earnings in the first quarter of 1998. In
previously issued financial statements, the Company recorded a charge for
purchased in-process R&D of $85.0 million in connection with the acquisition of
Shared. After discussions with the Staff of the Commission, the Company has
reduced the
                                       28
<PAGE>   29
 
amount of the write-offs for purchased in-process R&D to $63.0 million. This
reduction has been reallocated to goodwill. In addition, the Company reallocated
$51.0 million of the purchase price of Shared to other intangibles. The
Company's condensed consolidated financial statements have been restated to
reflect such adjustments as described herein and in Note 2 of the Notes to
Condensed Consolidated Financial Statements.
 
     In making its purchase price allocation, the Company relied on present
value calculations of income and cash flows, an analysis of project
accomplishments and completion costs, an assessment of overall contribution, as
well as project risk. The amounts assigned to the in-process R&D were determined
by identifying significant research projects for which technological feasibility
had not been established. In-process R&D included the development and deployment
of an innovative multi-service access platform, which will enable Shared to
provision new data services.
 
     Remaining development efforts for Shared projects include various phases of
design, development, and testing. Anticipated completion dates for the
in-process R&D projects will occur during the next two years, after which time
the Company expects to begin generating economic benefits from the technologies.
Expenditures to complete these projects are expected to total approximately $1.2
million in 1998 and $1.4 million in 1999.
 
     These estimates are subject to change, given the uncertainties of the
development process, and no assurance can be given that deviations from these
estimates will not occur. Management expects to continue development of these
efforts and believes the Company has a reasonable chance of successfully
completing the R&D programs. However, there is a risk associated with the
completion of the projects, and there is no assurance that any will meet with
either technological or commercial success. Failure to complete the in-process
R&D programs would result in the loss of the expected return inherent in the
fair value allocation.
 
     In connection with the purchase of DIGEX in the third quarter of 1997, the
Company allocated $60.0 million of the purchase price to in-process R&D projects
as described above under the caption "Quarter Ended September 30, 1998 Compared
to Quarter Ended September 30, 1997 -- Operating Expenses."
 
     Business restructuring and integration expense of approximately $51.9
million was recorded by the Company during the nine months ended September 30,
1998. The Company recorded a business restructuring and integration charge of
$50.1 million during the second quarter of 1998, which was comprised of
businesses exited, contract termination costs, and integration and other
restructuring costs. During the third quarter of 1998, the Company expensed
approximately $1.8 million in other business restructuring and integration
costs, which consist of businesses exited and integration and other
restructuring expenses, net of a $9.1 million reduction in business
restructuring costs associated with a contract negotiation. Such costs were
comprised primarily of network integration and information systems integration
costs. These costs represent incremental, redundant or convergence costs that
result directly from implementation of the Program, but are required to be
expensed as incurred. Such costs were substantially in line with the amounts
expected for the third quarter by management. Additional incremental, redundant
and convergence costs within this category of Program cost will be expensed as
they are incurred each quarter over the Program implementation period.
Management currently expects these additional costs to amount to approximately
$33.2 million over the remainder of the Program. Future cash outlays are
expected for all components of the remaining $12.1 million accrual (refer to
Note 4), with the exception of approximately $4.2 million for asset impairment
write-downs, which are expected to occur during the fourth quarter of 1998. The
Company expects future cash outlays of approximately $4.3 million during the
fourth quarter of 1998, $1.9 million during 1999, and the Company expects
approximately $1.7 million to occur evenly throughout the Program.
 
     The Company's condensed consolidated financial statements for the three and
nine month periods ended September 30, 1998 have been restated to reflect a
reduction of this charge by $7.9 million and 10.1 million, respectively,
primarily as a result of a contract negotiation during the third quarter as
described herein and in Note 2 of the Notes to Condensed Consolidated Financial
Statements.
 
                                       29
<PAGE>   30
 
Interest Expense
 
     Interest expense increased 278.7% to $151.1 million for the nine months
ended September 30, 1998 compared to $39.9 million for the same period in 1997.
This increase primarily resulted from interest expense on approximately $1.2
billion of senior notes issued from October 1, 1997, through the end of the
third quarter of 1998, plus the non-cash imputed interest charges of $5.1
million related to the acquisition of Shared and $1.0 million related to the
acquisition of National. In addition, the Company recorded interest expense of
$29.9 million during the nine months ended September 30, 1998, related to the
capital lease with Williams. Included in 1998 interest expense is $55.5 million
of debt discount amortization and $3.3 million of deferred loan cost
amortization, both of which are non-cash items. Interest expense capitalized in
connection with the Company's construction of telecommunications equipment
amounted to approximately $5.4 million and $2.5 million for the nine months
ended September 30, 1998 and 1997, respectively.
 
Other Income
 
     Other income increased 56.2% to $26.1 million for the nine months ended
September 30, 1998 compared to $16.7 million for the same period in 1997. This
increase was primarily the result of interest earned on the cash available from
the proceeds of the issuance of securities in 1997 and the exercise of the
over-allotment option with respect to the 8.5% Senior Notes in January 1998, the
issuance of the 8.6% Senior Notes in May 1998, and the issuance of the Series F
Preferred Stock in August 1998.
 
Extraordinary Loss
 
     The extraordinary loss of $43.8 million recorded during the third quarter
of 1997 consisted of pre-payment penalties relating to certain indebtedness
which was repaid from the proceeds of the offering of the 11 1/4% Senior Notes
issued in July of 1997 and the write-off of the unamortized deferred financing
costs associated with the indebtedness repaid.
 
Net Loss
 
     Net loss increased 83.9% to $370.1 million for the nine months ended
September 30, 1998 compared to $201.2 million for the same period in 1997. The
increase was principally due to the acquisition of Shared in the first quarter
of 1998 and National in the second quarter of 1998. In addition, the increased
operating expenses resulting from the expansion of the network, increased
selling, general and administrative costs, the charge for in-process R&D,
business restructuring and integration expenses, and increased interest costs
contributed to the increase in net loss.
 
Preferred Stock Dividends and Accretions
 
     Preferred stock dividends and accretions increased 151.2% to $68.1 million
for the nine months ended September 30, 1998 compared to $27.1 million for the
same period in 1997. The increase was due to the issuance of the two series of
preferred stock, October 1997 and August 1998, and the conversion of
approximately 15,000 shares of the Company's Series D Preferred Stock and
approximately 15,000 shares of the Company's Series E Preferred Stock into
Common Stock. The Company recorded a charge of approximately $11.0 million
during the third quarter of 1998 representing the market value of the inducement
feature of the conversions. Preferred stock dividends were paid in the form of
Common Stock and preferred stock. Management does not expect to pay cash
dividends in the foreseeable future.
 
EBITDA Before Certain Charges
 
     EBITDA before certain charges increased 138.5% to $15.4 million for the
nine months ended September 30, 1998 compared to $(39.9) million for the same
period in 1997. The increase was principally the result of the acquisitions of
Shared and LDS in the first quarter of 1998 and the acquisition of National in
the second quarter of 1998. These acquisitions contributed to improved EBITDA
before certain charges primarily by consolidating sales forces and introducing
the Company's products into additional markets. The Company
                                       30
<PAGE>   31
 
has continued its efforts to consolidate traffic through the Williams backbone
network, as well as, through the Company's existing networks in an efficient
manner. In addition, the Company has been successful in selling more of its
access lines "on switch" and increasing its mix of higher margin products. The
business restructuring and integration program has yielded benefits from the
elimination of redundant costs associated with rationalizing and integrating the
recent acquisitions. In addition, the Company has reduced network operation
expenses, facilities administration and maintenance expenses, and selling,
general and administrative expenses as a percentage of revenue in the six month
period ended September 30, 1998 as compared to the same period in 1997.
 
LIQUIDITY AND CAPITAL RESOURCES
 
     The Company's operations have required substantial capital investment for
the purchase of telecommunications equipment and the design, construction and
development of the Company's networks. Capital expenditures for the Company were
approximately $338.1 million and $178.7 million for the nine months ended
September 30, 1998 and 1997, respectively, excluding capital leases and
telecommunications equipment acquired in connection with business acquisitions.
The Company expects that it will continue to have substantial capital
requirements in connection with the (i) expansion and improvement of the
Company's existing networks, (ii) design, construction and development of new
networks, (iii) connection of additional buildings and customers to the
Company's networks, (iv) purchase of switches necessary for local exchange
services and expansion of interexchange services and (v) continued development
of the Company's enhanced data services. During the first quarter of 1998, the
Company utilized approximately $782.2 million of its available cash to complete
the Shared acquisition and approximately $33.2 million of its available cash to
complete the LDS acquisition. In addition, the Company utilized approximately
$64.4 million of its available cash to complete the acquisition of National in
April 1998.
 
     The Company has funded a substantial portion of these expenditures through
the public and private sale of debt and equity securities. From inception
through December 31, 1996, the Company raised approximately $212.6 million in
net proceeds from the sale of Common Stock, including Common Stock issued in
connection with certain acquisitions, and $324.6 million in net proceeds from
the sale of senior notes. During 1997 the Company raised approximately $957.7
million in net proceeds from the sale of senior notes and approximately $648.4
million in net proceeds from the sale of three series of preferred stock. During
1998, the Company raised approximately $537.3 million in net proceeds from the
sale of senior notes, including the over-allotment exercises, and approximately
$193.8 million in net proceeds from the sale of a series of preferred stock. All
of the Company's issued series of preferred stock include provisions that may
cause the securities to be redeemed upon a change of control of the Company. As
a result of these redemption provisions, the Company is required to classify the
preferred stock outside of stockholders' equity on the Company's condensed
consolidated balance sheet as of September 30, 1998. Additionally, none of the
outstanding series of preferred stock require the Company to pay cash dividends
in the foreseeable future.
 
     The substantial capital investment required to build the Company's network
has resulted in negative cash flow after consideration of investing activities
over the last five-year period. This negative cash flow after investing
activities is a result of the requirement to build a substantial portion of the
Company's network before connecting revenue-generating customers. The Company
expects to continue to produce negative cash flow after investing activities for
the next several years due to the continuous expansion and the development of
the Company's networks. Until sufficient cash flow after investing activities is
generated, the Company will be required to utilize its current and future
capital resources, including the issuance of additional debt and/or equity
securities, to meet its cash flow requirements.
 
     In response to the new pro-competitive telecommunications environment, the
Company accelerated and expanded its capital deployment plan to allow for an
increased level of demand-driven capital spending necessary to more rapidly
exploit the market opportunity in the local exchange market. The Company expects
to commit substantial amounts of funds to expand its existing network in order
to switch traffic within the local service area in those states where it is
currently permitted to provide such services. As of September 30, 1998, the
Company was certified as a CLEC in 36 states plus the District of Columbia,
allowing the Company to
 
                                       31
<PAGE>   32
 
provide local exchange services in those markets. The Company expects to expend
capital for the further development of the Company's enhanced data service and
interexchange service offerings.
 
     A portion of the Company's expansion has occurred, and may continue to
occur, by means of acquisitions. In July 1997, the Company acquired DIGEX, a
leading nationwide business ISP. The aggregate cash consideration for the
acquisition was approximately $160.0 million and was funded with the Company's
then existing cash reserves. In March 1998, the Company acquired Shared. The
total aggregate cash consideration for Shared was approximately $782.2 million,
which was paid out in 1998 and 1997, including certain transaction expenses and
fees relating to certain agreements. This amount includes repayment of $175.6
million of Shared's outstanding bank debt (including accrued interest and
outstanding fees) in connection with the consummation of the acquisition. In
March 1998, the Company completed its acquisition of LDS for a purchase price of
approximately $170.4 million, of which approximately $137.2 million was paid in
Common Stock and approximately $33.2 million was paid in cash, including the
repayment of approximately $15.1 million of LDS debt.
 
     On April 30, 1998, the Company completed the acquisition of privately held
National, an emerging switch-based competitive local exchange carrier and
established interexchange carrier. Aggregate consideration for the acquisition
was approximately $59.5 million in cash, plus 2,909,796 shares of the Company's
Common Stock valued at approximately $88.7 million, the retirement of $2.8
million in National's long-term debt, and $2.2 million in acquisition related
costs.
 
     During July and August 1998, the Company exchanged (a) approximately 2.029
million shares of its Common Stock for approximately 1.487 million Depositary
Shares (each representing a 1/100th interest in a share of Series D Preferred
Stock) and (b) approximately 1.423 million shares of its Common Stock for
approximately 1.511 million Depositary Shares (each representing a 1/100th
interest in a share of Series E Preferred Stock), pursuant to exchange
agreements with certain holders of such Depositary Shares.
 
     On August 18, 1998, the Company sold 8,000,000 Series F Depositary Shares
(aggregate liquidation preference $200 million) each representing a 1/100th
interest in a share of the Company's Series F Preferred Stock, in a private
placement transaction. Net proceeds to the Company amounted to approximately
$193.8 million. Dividends on the Series F Preferred Stock accumulate at a rate
of 7% of the aggregate liquidation preference thereof and are payable quarterly,
in arrears. Dividends are payable in cash or, at the Company's option, by
issuance of shares of Common Stock of the Company. The Series F Preferred Stock
is convertible, subject to prior redemption, at any time after November 16, 1998
at the option of the holder thereof into Common Stock of the Company. The Series
F Preferred Stock is redeemable, at the option of the Company, in whole or part,
at any time on or after October 17, 2001, at rates commencing with 104%,
declining to 100% on October 17, 2005.
 
     The Company expects that its EBITDA before certain charges will be positive
for 1998 and that its capital requirements (estimated at approximately $400.0
million, of which approximately $338.1 million has been expended during the
first nine months of 1998 which does not include the non-cash Williams network
capacity purchase) will be funded from available cash, cash generated from its
1998 operations, the bank credit facility discussed below and/or other offerings
of the Company's securities. The Company believes its business plan to be fully
funded through the end of 1999. Depending on market conditions, the Company may
determine to raise additional capital before such time. There can be no
assurance, however, that the Company will be successful in raising sufficient
debt or equity on terms that it will consider acceptable. Moreover, the terms of
the Company's outstanding indebtedness and preferred stock impose certain
restrictions upon the Company's ability to incur additional indebtedness or
issue additional preferred stock. The Company has entered discussions with
several banks for a bank credit facility, although there can be no assurance
that a bank facility on terms satisfactory to the Company will be established.
 
     The Company has from time to time held, and continues to hold, preliminary
discussions with (i) potential strategic investors (i.e. investors in the same
or a related business) who have expressed an interest in making an investment in
or acquiring the Company, (ii) potential joint venture partners looking toward
formation of strategic alliances that would expand the reach of the Company's
network or services without necessarily requiring an additional investment in or
by the Company and (iii) companies that
                                       32
<PAGE>   33
 
represent potential acquisition opportunities for the Company. There can be no
assurance that any agreement with any potential strategic investor, joint
venture partner or acquisition target will be reached nor does management
believe that any thereof is necessary to successfully implement its strategic
plans.
 
IMPACT OF YEAR 2000
 
     The Year 2000 issue is the result of computer-controlled systems using two
digits rather than four to define the applicable year. For example, computer
programs that have time-sensitive software may recognize a date ending in "00"
as the year 1900 rather than the year 2000. This could result in system failure
or miscalculations causing disruptions of operations including, among other
things, a temporary inability to process transactions, send invoices, or engage
in similar normal business activities.
 
     To ensure that its computer systems and applications will function properly
beyond 1999, the Company has implemented a Year 2000 program.
 
     As the first phase of its program, the Company conducted an inventory and
assessment of its network equipment, office equipment and information management
systems. While the Company believes that its equipment inventory is complete,
much of the equipment utilized by Intermedia resides outside the Company's
headquarters and there can be no assurance that mission critical equipment has
not been overlooked.
 
     Based on its inventory and assessment, the Company determined that it will
be required to modify or replace portions of its software and hardware so that
its networks, office equipment and information management systems will function
properly with respect to dates in the year 2000 and thereafter. Such
determinations were based, in part, on statements made by hardware and software
vendors used by the Company as to the year 2000 compliance of the systems
utilized by the Company. Intermedia also has conducted a risk assessment to
identify those systems whose failure would be expected to result in the greatest
risk to the Company. Although the Company intends to conduct tests to ensure
that its equipment is Year 2000 compliant, such tests will be focused
principally on those systems whose failure would pose the greatest risk to the
Company. Intermedia will likely not test all of its equipment and will rely upon
vendor representations, if received by the Company, where tests are not
conducted. There can be no assurance of the accuracy or completeness of such
vendor representations.
 
     The Company is in the process of contacting all of its significant
suppliers and large customers to determine the extent to which the Company's
interface systems are vulnerable to those third parties' failure to remediate
their own Year 2000 issues. The Company, however, has not undertaken an in-depth
evaluation of its suppliers' or customers' Year 2000 preparedness and the
ability of such third parties to adequately address their Year 2000 issues is
outside the Company's control. There can be no guarantee that the systems of
other companies on which the Company's systems rely will be timely converted or
that such conversions, if not completed or improperly implemented, would not
have a material adverse effect on the Company's systems.
 
     The Company is actively engaged in utilizing both internal and external
resources to reprogram, or replace, and test certain components of its networks
and information processing systems for Year 2000 compliance and scheduling the
installation of other necessary hardware and software upgrades. The Company's
objective has been to complete the Year 2000 project not later than December 31,
1998, which is prior to any anticipated impact on its operating systems. Though
the majority of the work will be completed by year-end, there are elements that
will not be completed until the second quarter of 1999 primarily due to limited
availability of compliant software and hardware. The Company believes that it
has allocated adequate resources for this purpose and expects its Year 2000 date
conversion program to be successfully completed on a timely basis. However,
there can be no assurance that it will successfully implement all of the
necessary upgrades in a timely manner. The Company presently believes that with
modifications to existing software and conversions to new software and hardware,
the Year 2000 issue will not pose significant operational problems for its
systems or have any adverse impact on the Company's customers or business units.
However, if such modifications and conversions are not made, or are not
completed in a timely fashion, the Year 2000 problems could have a material
impact on the operations of the Company.
 
                                       33
<PAGE>   34
 
     The 1998 cost of the Year 2000 project for the core Intermedia business is
estimated to be $0.8 million in external personnel costs and $0.7 million in
internal personnel costs, both of which are being funded from available cash.
This cost may be reduced if software and hardware are replaced with compliant
systems as a result of other currently scheduled capital projects. The remaining
expenses are not expected to have a material effect on the results of
operations. During the nine months ended September 30, 1998, the Company
incurred approximately $0.7 million in external staffing costs, $0.7 million in
internal staffing costs, and $0.2 million in hardware and software costs.
 
     Costs and timetables for Year 2000 projects associated with corporate
mergers and acquisitions are not included in the above estimates, and are funded
on a case-by-case basis as they occur. Total costs relating to systems
modification and testing associated with Year 2000 activities, including
hardware and software upgrades and personnel costs, relating to Intermedia
acquisitions is estimated to be $1.3 million for the fourth quarter of 1998.
Internal personnel costs associated with Year 2000 activities relating to the
Company's recent acquisitions were approximately $0.1 million for the third
quarter. It is projected that internal personnel costs associated with such Year
2000 activities relating to the acquisitions will be $0.1 million for fourth
quarter. Year 2000 compliance for Intermedia acquisitions will be accomplished
both by remediation of systems and by conversion to compliant Intermedia systems
as part of the Program. These cost estimates do not include the costs of system
conversions or upgrades that are included in the Program but which may also be
necessary to ensure Year 2000 compliance. Though some of these activities will
not be completed until the fourth quarter of 1999, the timing is not expected to
have any adverse impact on Intermedia customers or business units.
 
     Approximately $0.5 million was spent in the third quarter on upgrades to
the Company's hardware and software on an enterprise-wide basis. To date, $0.4
million has been spent on upgrades for the acquired companies. Projected costs
for the fourth quarter associated with hardware and software upgrades for the
acquisitions of Shared, DIGEX, LDS and National Tel are $0.3 million, largely in
shared tenant equipment and office infrastructure upgrades.
 
     The Company intends to develop appropriate contingency plans should certain
mission critical systems utilized by the Company or its significant suppliers
fail as a result of Year 2000 issues. In addition, the Company is participating
in industry wide efforts to address Year 2000 issues, the goal of which is to
develop contingency plans which address not only the Company's issues but those
of the telecommunications industry as a whole.
 
     These cost estimates do not include system upgrades that would otherwise
result as part of the Company's capital expenditure program associated with
integrating the acquired companies. The costs of the project and the date which
the Company has established to complete the Year 2000 modifications are based on
management's best estimates, which were derived utilizing numerous assumptions
of future events, including the continued availability of certain resources,
third party modification plans and other factors. However, there can be no
guarantee that these estimates will be achieved and actual results could differ
materially from those anticipated. Specific factors that might cause such
material differences include, but are not limited to, the availability and cost
of personnel trained in this area, the ability to locate and correct all
relevant computer codes, unanticipated mergers and acquisitions, and similar
uncertainties.
 
IMPACT OF INFLATION
 
     Inflation has not had a significant impact on the Company's operations over
the past 3 years.
 
     The information set forth above in "Management's Discussion and Analysis of
Financial Conditions and Results of Operations" include forward-looking
statements that involve numerous risks and uncertainties. Forward-looking
statements can be identified by the use of forward-looking terminology such as
"estimates," "projects," "anticipates," "expects," "intends," "believes," or the
negative thereof or other variations thereon or comparable terminology or by
discussions of strategy that involve risks and uncertainties. The Company's
actual results could differ materially from those anticipated in such
forward-looking statements as a result of certain factors, including those set
forth in the section entitled "Risk Factors" in the Company's Annual Report on
Form 10-K as amended for the year ended December 31, 1997.
 
                                       34
<PAGE>   35
 
                          PART II.   OTHER INFORMATION
 
ITEM 1.  LEGAL PROCEEDINGS
 
     Except as described below, the Company is not a party to any pending legal
proceedings other than various claims and lawsuits arising in the normal course
of business. The Company does not believe that these normal course of business
claims or lawsuits will have a material effect on the Company's financial
condition or results of operations.
 
     On June 20, 1997, two purported class action complaints were filed in the
Court of Chancery of the State of Delaware in and for New Castle County
respectively by TAAM Associates, Inc. and David and Chaile Steinberg, purported
stockholders of DIGEX on behalf of all non-affiliated common stockholders of
DIGEX against Intermedia, DIGEX and the DIGEX Directors. The cases have been
dormant since August 1997 when a motion to dismiss the Complaints was filed on
behalf of Intermedia, DIGEX and the DIGEX Directors. See Note 10 to the
Company's Condensed Consolidated Financial Statements included herein.
 
ITEM 2.  CHANGES IN SECURITIES
 
     On August 18, 1998, the Company sold 8,000,000 Series F Depositary Shares
(aggregate liquidation preference $200 million) each representing a
one-hundredth interest in a share of the Company's Series F Preferred Stock, in
a private placement transaction. Net proceeds to the Company amounted to
approximately $193.8 million. Dividends on the Series F Preferred Stock
accumulate at a rate of 7% of the aggregate liquidation preference thereof and
are payable quarterly, in arrears. Dividends are payable in cash or, at the
Company's option, by issuance of shares of Common Stock of the Company. The
Series F Preferred Stock is redeemable, at the option of the Company, in whole
or part, at any time on or after October 17, 2001, at rates commencing with
104%, declining to 100% on October 17, 2005.
 
     The Series F Preferred Stock is convertible, subject to prior redemption,
at the option of the holder thereof, at any time after November 16, 1998, into
Common Stock of the Company at a conversion price of $42.075 per share of Common
Stock, subject to certain adjustments.
 
     The Series F Depositary Shares were issued and sold to the initial
purchased pursuant to an exemption from registration provided by Section 4 (2)
of the Securities Act of 1933, as amended (the "Act"). Each of the initial
purchasers represented to the Company, among other things, that (i) it is a
qualified institutional buyer ("QIB"), (ii) it is not acquiring the Series F
Depositary Shares with a view to any distribution thereof that would violate the
Act or the securities laws of any state of the Untied States or any other
applicable jurisdiction, (iii) it will be re-offering and reselling the Series F
Depositary Shares only to QIBs in reliance on the exemption from the
registration requirements of the Act provided by rule 144A and to institutional
accredited investors in a private placement exempt from the registration
requirements of the Act, and (iv) no form of general solicitation or general
advertising has been or will be used by it or any of its representatives in
connection with the offer and sale of any of the Series F Depositary Shares.
 
     During July and August 1998, the Company exchanged approximately 2.029
million shares of Common Stock for approximately 1.487 million Depositary Shares
(each representing a 1/100th interest in a share of the Company's Series D
Preferred Stock) and approximately 1.423 million shares of Common Stock for
approximately 1.511 million Depositary Shares (each representing a 1/100th
interest in a share of the Company's Series E Preferred Stock) pursuant to
exchange agreements with certain holders of such Depositary Shares. The issuance
of the shares of Common Stock in exchange for the Depositary Shares was made in
reliance on the exemption from registration provided by Section 3 (a) (9) of the
Act for securities exchanged by an issuer with its existing security holders
exclusively. No commissions or other remuneration was paid or given for
soliciting such exchange.
 
ITEM 3.  DEFAULTS UPON SENIOR SECURITIES
 
     None.
 
                                       35
<PAGE>   36
 
ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
 
     None.
 
ITEM 5.  OTHER INFORMATION
 
     None.
 
ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K
 
     (a) Exhibits
 
<TABLE>
<CAPTION>
NUMBER        EXHIBIT
------        -------
<C>      <C>  <S>
  2.1    --   Agreement and Plan of Merger, dated as of June 4, 1997,
              among the Company, Daylight Acquisition Corp. and DIGEX.
              Exhibit 99 (c) (1) to the Company's Schedule 14D-1 filed
              with the Commission on June 11, 1997, is incorporated herein
              by reference.
  2.2    --   Agreement and Plan of Merger, dated as of November 20, 1997,
              among the Company, Moonlight Acquisition Corp. and Shared.
              Exhibit 99 (c) (1) to the Company's Schedule 14D-1 and
              Schedule 13D filed with the Commission on November 26, 1997,
              is incorporate herein by reference.
  2.3    --   Acquisition Agreement, dated as of December 17, 1997, among
              the Company and the holders of interests in the Long
              Distance Savers companies. Exhibit 2.3 to Amendment No. 1 to
              the Company's Registration Statement on Form S-3 filed with
              the Commission on January 14, 1998 (No. 333-42999) is
              incorporated herein by reference.
  2.4    --   Agreement and Plan of Merger, dated as of February 11, 1998,
              among the Company, Sumter One Acquisition, Inc., Sumter Two
              Acquisition, Inc., National Telecommunications of Florida,
              Inc., NTC, Inc. and the stockholders of National. Exhibit
              2.4 to the Company's Registration Statement on Form S-3
              filed with the Commission on February 13, 1998 (No.
              333-46369) is incorporated herein by reference.
  4.1    --   Certificate of Designation of Voting Power, Designation
              Preferences and Relative, Participating, Optional and Other
              Special Rights and Qualifications, Limitations and
              Restrictions of 7% Series F Junior Convertible Preferred
              Stock of the Company, filed with the Secretary of State of
              the State of Delaware on August 17, 1998. Exhibit 4.8 to the
              Company's Registration on Form S-3 filed with the Commission
              on September 4, 1998 (No. 333-62931) is incorporated herein
              by reference.
  4.2    --   Registration Rights Agreement, dated as of August 18, 1998,
              among the Company and the initial purchasers of the Series F
              Depositary Shares. Exhibit 4.7 to the Company's Registration
              on Form S-3 filed with the Commission on September 4, 1998
              (No. 333-62931) is incorporated herein by reference.
  4.3    --   Deposit Agreement, dated as of August 18, 1998, among the
              Company and the Continental Stock and Transfer & Trust
              Company. Exhibit 4.9 to the Company's Registration on Form
              S-3 filed with the Commission on September 4, 1998 (No.
              333-62931) is incorporated herein by reference.
 27.1    --   Financial Data Schedule (For Commission Use Only).
</TABLE>
 
     (b) Reports on Form 8-K
 
     The following reports on Form 8-K were filed during the third quarter of
1998:
 
          The Company filed a Current Report on Form 8-K, dated August 4, 1998,
     reporting under Item 5 that it had exchanged approximately 2.029 million
     shares of Common Stock for approximately 1.487 million Depositary Shares
     (each representing a 1/100% interest in a share of Series D Preferred
     Stock) and approximately .665 million shares of Common Stock for
     approximately .710 million Depositary Shares (each representing a 1/100%
     interest in a share of Series E Preferred Stock), pursuant to exchange
     agreements with certain holders of Depositary Shares and (b) that it
     commenced a private offering of $200 million liquidation preference of
     Series F Depositary Shares.
 
                                       36
<PAGE>   37
 
          The Company filed a Current Report on Form 8-K, dated August 21, 1998,
     reporting under Item 5 the consummation of a private offering of $200
     million liquidation preference of Series F Depositary Shares.
 
          The Company filed a Current Report on Form 8-K, dated September 3,
     1998, filing under Item 7 unaudited pro forma condensed consolidated
     financial statements giving effect to the Company's acquisitions of
     National, LDS, Shared and DIGEX and its 1997 debt and equity offerings.
 
                                       37
<PAGE>   38
 
                                   SIGNATURES
 
     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this amendment to be signed on its behalf by the
undersigned thereunto duly authorized.
 
Dated: January 29, 1999
 
                                          INTERMEDIA COMMUNICATIONS INC.
                                                       (Registrant)
 
                                                 /s/ JEANNE M. WALTERS
                                          ----------------------------------
                                                    Jeanne M. Walters
                                              Vice President, Controller and
                                                 Chief Accounting Officer
 
                                       38