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                                                                    EXHIBIT 10.1


                       [ZIFF DAVIS MEDIA INC. LETTERHEAD]


                                January 19, 2001

ZDNet, Inc.
CNET Networks, Inc.
28 East 28th Street
New York, NY 10016
Attention: Daniel Rosensweig

     Re: Amendment to License Agreement

Dear Dan:

     This letter agreement (this "Agreement") amends certain terms of the
License Agreement (the "License Agreement") dated as of April 5, 2000 by and
between ZDNet, Inc., formerly Ziff-Davis Inc., a Delaware corporation ("ZDNet"),
and Ziff Davis Media Inc., a Delaware corporation ("Ziff Davis Media"), and sets
forth certain other agreements between the parties hereto. Capitalized terms
used in this Agreement and not otherwise defined will have the meanings ascribed
to such terms in the License Agreement. ZDNet, CNET Networks, Inc. ("CNET"), and
Ziff Davis Media agree as follows:

A.   LICENSE AGREEMENT


     1.   The License Agreement, including the licenses granted by Ziff Davis
          Media to ZDNet thereunder with respect to both U.S. and foreign
          Publications, will terminate and be of no further force or effect on
          midnight February 28, 2002 (the "License Agreement Termination Date").
          From and after the License Agreement Termination Date, neither ZDNet,
          CNET, nor any of their affiliates, successors, assigns or licensees
          will have any right to (i) translate, reproduce, publicly display,
          transmit or distribute Content (including, without limitation,
          archival Content of the Publications), except as permitted by fair use
          or other similar laws, or (ii) use the Trademarks. Notwithstanding the
          foregoing, Sections 10, 11, 14, 16(i), the second sentence of 16(ii),
          16(iii) and 18 of the License Agreement will survive the expiration or
          termination of the License Agreement.

     2.   Ziff Davis Media's obligation in Section 1(i) of the License Agreement
          to cause the purchaser of any Publication to agree to assume and carry
          out the obligations of Ziff Davis Media under the License Agreement
          with respect to that Publication



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          shall continue until the License Agreement Termination Date and any
          purchaser shall also assume all of Ziff Davis Media's obligations
          under this Agreement that pertain to such Publication.

     3.   (a) The licenses granted to ZDNet under the License Agreement to
          translate, reproduce, publicly display, transmit or distribute Content
          online and through electronic distribution via the World Wide Web, the
          Internet or any technology hereafter developed and used for similar
          purposes or evolutions or migrations thereof, to grant third parties
          the right to distribute Content as described above (including Content
          from the non-U.S. Publications) and to use the Trademarks in
          connection therewith, shall remain exclusive through and including
          February 28, 2001.

          (b)  Effective March 1, 2001 and continuing through the License
               Agreement Termination Date, any and all exclusive licenses under
               the License Agreement shall become non-exclusive, and ZDNet and
               CNET, on the one hand, and Ziff Davis Media and its affiliates,
               on the other hand, shall have the non-exclusive right to, and
               (subject to the limitations set forth elsewhere in this Paragraph
               3 and the other requirements set forth in the License Agreement
               as amended by this Agreement) the right to grant licenses to
               third parties to, translate, reproduce, publicly display,
               transmit or distribute Content through any means or media,
               including, without limitation, electronic distribution via the
               World Wide Web, the Internet or any technology hereafter
               developed and used for similar purposes or evolutions or
               migrations thereof. Effective March 1, 2001 and continuing
               through the License Agreement Termination Date, the Content may
               be used by both ZDNet and CNET as permitted by the terms of the
               License Agreement as amended by this Agreement. If for any
               reason, Ziff Davis Media does not provide any Publication Content
               to ZDNet in accordance with the manner and timing of distribution
               prior to the date hereof or in accordance with the requirements
               of Paragraph 3(e), then, neither Ziff Davis Media nor any if its
               affiliates shall use itself, or permit any third party to use, in
               any manner online, the Content which has not been so delivered
               until such time as it has been delivered to ZDNet. The preceding
               sentence shall be ZDNet's sole remedy with respect to any failure
               by Ziff Davis Media to deliver Content from the PC Expert
               Publication in France, however, it shall be ZDNet's non-exclusive
               remedy, in addition to any breach of contract or other claim,
               with regard to any failure to provide Content from any
               Publication other than PC Expert.

          (c)  Notwithstanding the foregoing or anything to the contrary
               contained in the License Agreement, but subject to Ziff Davis
               Media's rights under Section 1(ii) of the License Agreement, Ziff
               Davis Media shall not license Content from any of the
               Publications to any of the third parties identified as Tier 1



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               listed on the attached Schedule 1 until March 1, 2002, or to any
               of the third parties identified as Tier 2 listed on the attached
               Schedule 1 until December 1, 2001, in each case, as such Schedule
               may be modified from time to time by written notice from ZDNet to
               reflect new sublicenses of Content as permitted below. The
               content sublicenses with the parties listed on Schedule 1 are
               referred to as the "Restricted Arrangements". During the period
               from March 1, 2001 through March 1, 2002, ZDNet will have the
               continuing right under, and subject to the terms and conditions
               of, Section 2 of the License Agreement to enter into new Content
               sublicense arrangements, to add those arrangements to Schedule 1
               and such new arrangements shall be considered Restricted
               Arrangements (but only to the extent such sublicenses were
               entered into after the date of this Agreement and only with
               respect to entities which Ziff Davis Media has not notified ZDNet
               that it has a Content license agreement with), provided that in
               all events ZDNet's right to license the Content (and the licenses
               so granted as they apply to the Content) shall terminate on the
               License Agreement Termination Date. Until the License Agreement
               Termination Date, each party shall provide the other party with
               written notification of all new third party Content license
               agreements within five (5) days of entering into such
               arrangements. Notwithstanding the foregoing, until March 1, 2002,
               neither ZDNet or CNET, on the one hand, nor Ziff Davis Media or
               its affiliates on the other hand, will license any Publication
               Content to any of the following entities or their affiliates (as
               such term is defined in Section 13): International Data Group,
               Inc., CMP Media, Inc., United News & Media PLC, or Imagine Media,
               Inc. The preceding list of entities shall replace in its entirety
               the list of Ziff Davis Media competitors in Schedule 7.1(i)
               referred to in Section 2(i)(A) of the License Agreement.

          (d)  Notwithstanding anything in this Agreement to the contrary, ZDNet
               will remain obligated to make the royalty payments to Ziff Davis
               Media contemplated by the last paragraph of Section 2(i) of the
               License Agreement in respect of the Restricted Arrangements.

          (e)  From March 1, 2001 through the License Agreement Termination
               Date, Ziff Davis Media shall provide ZDNet with Content from the
               Publications as soon as the particular issue (or portion thereof)
               is completed for transmission to the printer, or on such earlier
               date as any item of Content is released in any media. In the
               event that issues or specific stories are marked with an embargo
               date that applies universally to Ziff Davis Media and all of its
               licensees, ZDNet agrees to honor such embargo dates and to ensure
               that the information remains confidential until those dates.

     4.   (a) ZDNet's right and obligation to host the Websites of each U.S.
          Publication as provided in Section 3 of the License Agreement and
          ZDNet's license to use the



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          Trademarks (including, without limitation, the urls) which relate to
          each U.S. Publication, will terminate with respect to each particular
          U.S. Publication in accordance with the following schedule:

<TABLE>
<CAPTION>
                                          Website Hosting
         Publication                      Termination Date
         -----------                      ----------------

<S>                                       <C>
Family PC                                 April 1, 2001

Yahoo! Internet Life,                     May 1, 2001
Computer Gaming World,
Expert Gamer, Electronic
Gaming Monthly, Official
U.S. Playstation Magazine

PC Magazine                               July 1, 2001

Interactive Week                          September 1, 2001

Ziff Davis Smart Business for             October 1, 2001
the New Economy; eWeek

Smart Partner                             November 1, 2001
</TABLE>

          ZDNet's right and obligation to host the Websites of each non-U.S.
          Publication as provided in Section 3 of the License Agreement and
          ZDNet's license to use the Trademarks (including, without limitation,
          the urls) which relate to each non-U.S. Publication, will terminate
          with respect to each particular non-U.S. Publication on the License
          Agreement Termination Date (which License Agreement Termination Date
          shall be deemed the Website Hosting Termination Date (as defined
          below) for the non-U.S. Publications for purposes of this Agreement).
          On the applicable date on which ZDNet's Website hosting rights and
          obligations and Trademark licensing rights terminate with respect to a
          particular Publication (each, a "Website Hosting Termination Date"),
          as between ZDNet/CNET and Ziff Davis Media, only Ziff Davis Media and
          its affiliates will have the right to host, maintain and produce the
          Website with respect to the applicable Publication and to use
          exclusively the applicable Trademarks.

          (b) ZDNet will continue to post the ZDNet home page links described in
          Section 3(v)(A) of the License Agreement for a particular Publication
          until the Website Hosting Termination Date for such Publication.
          Beginning on the first Website Hosting Termination Date, ZDNet and
          CNET, on the one hand, and Ziff Davis Media and its affiliates, on the
          other hand, will display statements that such party's Websites are not
          affiliated with the Websites of the other party, as well as



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          links directing users to the other party's Websites. The links shall
          be posted for a period of 120 days from each applicable Website
          Hosting Termination Date in a form to be mutually agreed upon by the
          parties. The links will be located on each page of any Website of Ziff
          Davis Media or its affiliates which includes Publication Content and
          each page of any Website of ZDNet or CNET which includes Publication
          Content. The links on the Ziff Davis Media and affiliates' Websites
          will be of the same size and placement on the page as those on the
          ZDNet and CNET Websites, such size, design and placement shall be
          mutually agreed upon by the parties.

          (c) On the Website Hosting Termination Date for Yahoo! Internet Life,
          ZDNet will deliver to Ziff Davis Media an archive in XML format of the
          Daily Net Buzz, Joke of the Day, and the other daily Yahoo! Internet
          Life content linked to from the home page of that Publication Website
          (the "YILO Daily Content") which will include the YILO Daily Content
          for the one year period prior to such Website Hosting Termination
          Date. On the Website Hosting Termination Date for PC Magazine, ZDNet
          will deliver to Ziff Davis Media an archive in XML format of the PC
          Magazine First Looks (the "First Looks") which will include the First
          Looks for the one year period prior to such Website Hosting
          Termination Date.

     5.   (a) For the period prior to the applicable Website Hosting Termination
          Date, Section 3(ii) is hereby modified such that ZDNet will not be
          obligated to make any enhancements or material modifications to the
          Publication Websites (other than bug fixes and technical upgrades)
          beyond such Websites current form, unless approved by ZDNet (which
          approval will not be unreasonably withheld or delayed) and paid for by
          Ziff Davis Media. For purposes of clarity, the preceding sentence
          shall not limit ZDNet's right to cease enhancements as permitted under
          Paragraph 6 below. Notwithstanding the foregoing, but assuming Ziff
          Davis Media's compliance with its obligations below to make any former
          ZDNet employees it hires available for services, ZDNet agrees to post
          material on the Publication Websites in a timely fashion until each
          applicable Website Hosting Termination Date.

          (b)  Effective on each applicable Website Hosting Termination Date,
               ZDNet's obligations under Section 3(iv) of the License Agreement
               that pertain to Publication email newsletter distribution for the
               applicable Publication Website shall terminate and ZDNet shall
               have no further obligations thereunder with respect to such
               Publication Website. Effective on March 1, 2001, ZDNet shall no
               longer have any obligation to acquire additional subscribers for
               such newsletters, but shall continue to include newsletter
               subscriptions as part of its registration process until the
               applicable Website Hosting Termination Date.



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          (c)  If, prior to a Website Hosting Termination Date, Ziff Davis Media
               hires (or has hired) a ZDNet employee who had worked for ZDNet in
               connection with the hosting or production of a Publication
               Website, Ziff Davis Media will make such employee reasonably
               available to ZDNet to assist in performing his or her prior
               responsibilities for such Publication Website, until the Website
               Hosting Termination Date for such Publication. ZDNet shall have
               no further obligation to provide, or to provide Ziff Davis Media
               funding for, any editorial positions for the Publication Websites
               pursuant to Section 3(vi) of the License Agreement. The preceding
               sentences shall not affect ZDNet's obligation to continue hosting
               and posting Content for each Publication Website, or to continue
               to fund such hosting and posting, until the applicable Website
               Hosting Termination Date.

     6.   For the period prior to the applicable Website Hosting Termination
          Date, the second sentence of Section 3(iii) is hereby modified such
          that ZDNet will continue to have the right (but not the obligation) to
          include content it creates or licenses in a Publication Website, but
          only to the extent ZDNet currently includes such additional content.
          All other provisions of Section 3(iii) shall terminate with respect to
          a particular Publication Website on the applicable Website Hosting
          Termination Date. ZDNet's obligations in Section 3(viii) of the
          License Agreement regarding the payment to Yahoo! of twenty percent of
          Advertising Revenue and regarding ZDNet's obligation to host that
          Publication Website shall terminate on the Website Hosting Termination
          Date for the Yahoo! Internet Life Publication. The parties'
          obligations under Section 4 of the License Agreement shall terminate
          effective as of March 1, 2001.

     7.   ZDNet will continue to make royalty payments to Ziff Davis Media
          pursuant to Section 5 of the License Agreement for all periods through
          March 1, 2001. The final royalty payment (in respect of January and
          February 2001) will be made not later than March 25, 2001. For
          purposes of clarity, the royalty payments will be calculated as
          described in such section taking into account solely the gross
          revenues of ZDNet and its subsidiaries (subject to the exclusions
          listed in such section ) and will not include the revenues of the
          other businesses of CNET. From and after the License Agreement
          Termination Date, ZDNet will not be obligated to make any royalty
          payments under Section 5 of the License Agreement. In consideration of
          the elimination, after March 1, 2001, of all royalty obligations under
          Section 5 of the License Agreement, ZDNet shall pay Ziff Davis Media a
          License Agreement termination fee in the total amount of $4.5 million,
          payable in cash as follows: $2.2 million due on March 1, 2001, and
          $2.3 million due on March 1, 2002.



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     8.   ZDNet's rights under the first sentence of Section 6(i) of the License
          Agreement will terminate on March 1, 2002 and may be exercised by
          either ZDNet or its affiliates, including, CNET. Ziff Davis Media's
          obligations under Section 6(i) of the License Agreement to include the
          urls of the Publication Websites hosted by ZDNet on the cover and the
          table of contents of the Publication shall end on the applicable
          Website Hosting Termination Date. Ziff Davis Media's obligation in
          Section 6(i) to include subscription offers for ZDNet newsletters
          within its subscription signups shall end on March 1, 2001.

     9.   ZDNet will continue to include online subscription forms for each
          Publication on the Publication Website until the Website Hosting
          Termination Date for such Publication. In addition, ZDNet will
          distribute one mailing per month until the applicable Website Hosting
          Termination Date to the ZDNet announce list. Such mailing will promote
          subscription offers for any Publication still hosted by ZDNet on the
          date such announce mailing is distributed. Ziff Davis Media will
          create the content of the mailings, however, it will be subject to
          ZDNet's reasonable prior review and approval. Ziff Davis Media will
          pay to ZDNet $5.00 per net subscriber (both controlled and paid)
          generated as a result of such mailings. Net subscriptions for
          Publications with a paid circulation means subscriptions for which the
          subscriber actually pays and for Publications with controlled
          circulation means subscriptions for which the subscriber actually
          qualifies. Payment shall be made to ZDNet within thirty (30) days
          after the end of each calendar quarter (for example, on April 30, 2001
          for the period through March 31, 2001) and ZDNet shall have the same
          rights of audit with respect the payments owed to it under this
          Paragraph 9 that are given to Ziff Davis Media under Section 5(iii) of
          the License Agreement. Ziff Davis Media will have the right to set the
          terms and rates of such subscription offers. The provisions of
          Sections 6(ii) and 6(iii) of the License Agreement will terminate on
          March 1, 2001 and neither party shall have any continuing obligations
          under such Sections from and after such date.

     10.  From and after March 1, 2001, the obligations of each party under
          Section 7 of the License Agreement will terminate and such Section 7
          will have no further force or effect.

     11.  Section 8(iii), Section 8(iv) and Section 17 of the License Agreement
          are hereby deleted in their entirety effective as of March 1, 2001 and
          neither party will have any further obligations thereunder.

     12.  Section 10(v) of the License Agreement is hereby modified such that
          the measure of the cap on Ziff Davis Media's liability for damages
          shall be the larger of (a) the amount of royalties paid to Ziff Davis
          Media in the contract year preceding the claim, and (b) $6.5 million
          (such larger amount, the "Liability Cap"). In addition, the Liability
          Cap shall not apply to Ziff Davis Media's



<PAGE>   8



          liability for any willful breach of the License Agreement as amended
          by this Agreement.

     13.  From and after the date of this Agreement, Section 12 of the License
          Agreement shall be deleted and such Section 12 will have no further
          force or effect; provided, however, that the licenses granted to ZDNet
          under the License Agreement (as amended by this Agreement) are
          personal to ZDNet and CNET, and may not be assigned by ZDNet or CNET
          except in connection with the sale or transfer of all or substantially
          all of their assets or businesses, or the merger into another entity,
          where the surviving entity agrees to be bound by the provisions of
          this Agreement, provided that this Agreement may not be assigned in
          whole or in part, including by operation of law, to International Data
          Group, Inc., CMP Media, Inc., United News & Media PLC, or Imagine
          Media, Inc., or any of their affiliates (defined for purposes of this
          paragraph as any entity which is controlled by, controls or is under
          common control with any of the named entities).

     14.  Section 18(i)(a) of the License Agreement shall be amended so that all
          notices to Ziff Davis Media will be sent in care of Ziff Davis Media,
          Inc., 28 East 28th Street, 14th floor, New York, New York 10016,
          Attention: Chief Executive Officer, with a copy sent to the same
          address to the attention of the company's General Counsel.


B.   MISCELLANEOUS

     1.   CNET and ZDNet will be jointly and severally liable for all
          obligations, including without limitation payment obligations, of
          ZDNet under the License Agreement and this Agreement.

     2.   Ziff Davis Media, on behalf of itself and its subsidiaries and
          affiliates, hereby waives any and all breaches of, defaults under, or
          failures to comply with the terms and conditions of, the License
          Agreement by ZDNet which have occurred on or before the date of this
          Agreement and each hereby releases each of CNET and ZDNet and their
          respective affiliates from liability with respect to such waived
          matters, including any claims arising out of, resulting from or
          relating to the Yahoo! Agreement prior to the date of this Agreement;
          provided, however, that such waiver and release is a one-time waiver
          and release and will not waive or release future compliance with the
          terms of the License Agreement as amended by this Agreement. This
          waiver is limited as specified and will not constitute a modification
          or amendment to any provision of the License Agreement.

     3.   CNET and ZDNet, on behalf of themselves and their subsidiaries and
          affiliates, hereby waive any and all breaches of, defaults under, or
          failures to comply with



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          the terms and conditions of, the License Agreement by Ziff Davis Media
          or Ziff Davis Publishing which have occurred on or before the date of
          this Agreement, and each hereby releases each of Ziff Davis Media and
          Ziff Davis Publishing and their respective affiliates from liability
          with respect to such waived matters, including any claims arising out
          of, resulting from or relating to any failure of Ziff Davis Media to
          provide or make available to ZDNet prior to or after the date of this
          Agreement, Content from the PC Expert Publication in France; provided,
          however, that such waiver and release is a one-time waiver and release
          and will not waive or release future compliance with the terms of the
          License Agreement as amended by this Agreement (except as specified
          above with respect to the PC Expert Publication). This waiver is
          limited as specified and will not constitute a modification or
          amendment to any provision of the License Agreement.

     4.   Except as modified by this Agreement, the License Agreement will
          continue in full force and effect in accordance with its terms. To the
          extent that this Agreement contains terms, conditions or agreements
          which are different from, in addition to or are inconsistent with the
          terms of the License Agreement, the terms of this Agreement will
          govern. This Agreement will be governed by and construed in accordance
          with the law of the State of New York applicable to agreements made
          and to be performed in New York. Each party agrees that any action or
          proceeding brought by the other during or after the term of this
          Agreement arising out of or related to this Agreement shall be brought
          in courts located in the State of New York. Each party irrevocably
          consents to the jurisdiction of the courts of the State of New York
          and of any Federal Court located in New York in connection with any
          action or proceeding brought during or after the term of this
          Agreement and arising out of or related to this Agreement and waives
          any objection to venue or any claim that the action is brought in an
          inconvenient forum. This Agreement may be executed in one or more
          counterparts and may be executed by facsimile signature.

     5.   Except as may be required by law or the rules of any applicable
          securities exchange, no party to this Agreement shall make, nor permit
          its controlled affiliates to make any public statements about this
          Agreement or the License Agreement without the prior approval of the
          other party, which shall not be unreasonably withheld or delayed.

     Please have an authorized representative of ZDNet and CNET sign below to
indicate your agreement with the foregoing.



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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their officers duly authorized as of the date first written above.

                                       ZIFF DAVIS MEDIA INC.


                                       By:
                                          ----------------------------
                                          Name:
                                          Title:


                                       ZDNET, INC.


                                       By:
                                          ----------------------------
                                          Name:
                                          Title:


                                       CNET Networks, Inc.


                                       By:
                                          ----------------------------
                                          Name:
                                          Title: