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                                                         Exhibit 10.29

                                   PROMISSORY NOTE

New York, New York
US$340,000,000                                    November 30, 1999


     THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
     AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY NOT BE REOFFERED OR
     SOLD UNLESS AN EXEMPTION FROM REGISTRATION IS AVAILABLE.

          FOR VALUE RECEIVED, NATIONAL BROADCASTING COMPANY,  INC., a Delaware
corporation ("MAKER"), by this promissory note (the "NOTE") unconditionally
promises to pay to the order of GE INVESTMENTS SUBSIDIARY, INC., a Delaware
corporation (the "HOLDER"), the principal sum of Three Hundred Forty Million
United States Dollars (US$340,000,000), together with interest at the rate of
five percent (5.4%) per annum on the unpaid principal balance from the date
hereof to the date such principal balance is paid in full, as set forth in
paragraph 2 below.  The principal amount, plus interest thereon, shall be due
and payable in sixteen (16) equal installments of $23,770,121 each, payable on
each February 30, May 30, August 30 and November 30 thereafter (each, a "PAYMENT
DATE"), until November 30, 2003.  Any principal, interest or any other amount
hereunder which is not paid when due (whether as stated, by acceleration or
otherwise) shall, to the extent permitted by law, thereafter bear interest at
the rate per annum 2% above the rate described above.

                                 TERMS AND PROVISIONS

     1.  PAYMENTS.  All payments to be made hereunder by the Maker shall be
made without set-off or counterclaim, in United States dollars in immediately
available funds at such place as may be designated by the Holder in writing
from time to time.  The Holder is hereby authorized to record the date and
amount of each payment of principal and interest, and other information with
respect thereto, consistent with customary practices, and following each such
recordation to provide the Maker with written notification of such
recordation, and any such recordation and written notification shall
constitute PRIMA FACIE evidence, absent manifest error, of the accuracy of
the information so recorded and notified; PROVIDED, HOWEVER, that the failure
to make a notation or the inaccuracy of any notation shall not limit or
otherwise affect the obligations of the Maker under this Note. Whenever any
payment hereunder shall be stated to be due on a day that is not a Business
Day, such payment shall be made on the succeeding Business Day.  "BUSINESS
DAY" shall mean a day other than a Saturday, Sunday or other day on which
commercial banks in New York City are authorized or required by law to close.

     2.  INTEREST.  Interest shall be computed on the basis of a year of 365
days for actual days elapsed and shall be payable from the date hereof on
each Payment Date until maturity (whether as stated, by acceleration or
otherwise), on demand in respect of any past due amount and upon payment in
full of this Note.  Interest shall accrue and be paid by the Maker in arrears
on each

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Payment Date until maturity.  Anything in this Note to the contrary
notwithstanding, the Holder shall not be permitted to charge or receive, and
the Maker shall not be obligated to pay, interest in excess of the maximum
rate from time to time permitted by applicable law.

     3.  PREPAYMENT.  The Maker shall have the right to prepay this Note in
whole or in part at any time, without premium or penalty, provided such
prepayment is accompanied by the payment of all unpaid interest accrued to
the date of prepayment and any other amounts then due under this Note, and
any such partial prepayment will trigger a recalculation by the Holder of the
amount of the installment owed on the remaining payment dates, provided that
the remaining installments shall be in equal amounts.

     4.  REPRESENTATIONS AND WARRANTIES OF THE MAKER.  The Maker hereby
represents and warrants to the Holder that: (a) the Maker is duly organized,
validly existing and in good standing under the laws of its jurisdiction of
organization, has the full power and authority, and the legal right, to make,
deliver and perform the Note and its obligations hereunder on the terms and
conditions hereof and has taken all necessary corporate action to authorize
the execution, delivery and performance of the Note and to authorize the
borrowing hereunder, and this Note has been duly executed and delivered on
behalf of the Maker; (b) this Note constitutes a legal, valid and binding
obligation of the Maker enforceable against it in accordance with its terms,
except as enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting the enforcement of
creditors' rights generally and by general equitable principles (whether
enforcement is sought by proceedings in equity or at law); (c) the execution,
delivery and performance of this Note, the borrowing hereunder and the use of
the proceeds thereof will not violate any material requirement of law, any
material contractual obligation of the Maker or its subsidiaries or any of
their applicable charters, bylaws or similar documents; and (d) no Event of
Default (as defined below) has occurred and is continuing.

     5.  REPRESENTATIONS AND WARRANTIES OF THE HOLDER.  The Holder hereby
represents and warrants to the Maker that: (a) the Holder is duly organized,
validly existing and in good standing under the laws of its jurisdiction of
organization, has the full power and authority, and legal right, to make the
loan to the Maker evidenced by this Note and has taken all necessary
corporate action to authorize the making of such loan, and this Note has been
duly executed by the Holder; (b) the Holder is an "accredited investor"
within the meaning of Regulation D of the Securities Act and is being issued
this Note for its own account and not with a view to the distribution thereof
in violation of the Securities Act; (c) the Holder understands and
acknowledges that this Note has not been registered pursuant to the
provisions of the Securities Act and may be offered and resold only if
registered pursuant to the provisions of the Securities Act or if an
exemption from registration is available, except under circumstances where
neither such registration nor such exemption is required by law, and that the
Maker is not required to register this Note; and (d) the Holder has had
access to such financial and other information concerning the Maker as it
deemed necessary in connection with the issuance of this Note.

     6.  EVENTS OF DEFAULT.  If (a) the Maker fails to pay when due any
principal of or interest on this Note or any other amount payable hereunder;
or (b) the Maker admits in writing its inability to pay its debts generally;
makes a general assignment for the benefit of creditors; has

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any proceeding instituted by or against it seeking to adjudicate it as
bankrupt or insolvent, or seeking liquidation, winding up, reorganization,
arrangement, adjustment, protection, relief, or composition of the Maker or
its debts under any law relating to bankruptcy, insolvency or reorganization
or relief of debtors, or seeking the entry of an order for relief or the
appointment of a receiver, trustee, or similar official for it or any
substantial part of its property; provided, in the case where such proceeding
is involuntarily instituted against the Maker, such proceeding remains
undismissed after 30 days; or (c) any representation or warranty made by the
Maker in this Note is false or misleading in any material respect; then, and
in any such event (each, an "Event of Default"), the Holder may, by notice of
default given to the Maker in writing or by facsimile transmission, declare
unpaid principal, accrued interest and all other amounts payable under this
Note to be immediately due and payable without presentment, demand, protest
or other notice of any kind, each of which is hereby expressly waived by the
Maker.

     7.  NO WAIVER.  No action or omission by the Holder shall constitute a
waiver of any rights or remedies of the Holder hereunder.  Such rights and
remedies are cumulative and not exclusive of any rights or remedies provided
by law.

     8.  AMENDMENT; ASSIGNMENT. The terms of this Note may be amended,
supplemented or modified only with the written consent of the Maker and the
Holder.  This Note shall be binding upon and inure to the benefit of the
Maker, the Holder and their respective successors and assigns, except that
neither the Holder nor the Maker may assign or transfer any of its rights or
obligations under this Note without the prior written consent of the other
party.  In the event of any assignment or transfer by the Holder (including
any assignment or transfer to NBC Internet, Inc.) with the prior written
consent of the Maker, the Maker shall, upon the request of the transferee and
receipt of this Note from transferee, reissue this Note in the name of the
transferee.

     9.  GOVERNING LAW; JURISDICTION.  This Note is made and delivered in New
York, New York, and, pursuant to Section 5-1401 of the General Obligations
Law of the State of New York, shall be governed by and construed and
interpreted in accordance with the laws of the State of New York applicable
to contracts fully performed in New York.  All judicial actions, suits or
proceedings brought against Maker or the Holder with respect to its
obligations, liabilities or any other matter under or arising out of or in
connection with this Note or for recognition or enforcement of any judgment
rendered in any such proceedings shall be brought exclusively in any state or
federal court located in the County of New York.

     10.  MUTILATED, DESTROYED OR MISSING NOTES.  If any mutilated Note is
surrendered to the Maker or the Maker receives evidence to its satisfaction
of the destruction, loss or theft of the Note, the Maker shall issue a
replacement Note.  If required by the Maker, an indemnity bond must be
supplied by the Holder that is sufficient in the judgment of the maker to
protect the Maker from any loss it may suffer if the Note is replaced.  The
Maker may charge for any expenses in replacing the Note.




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                                          NATIONAL BROADCASTING COMPANY, INC.



                                       By: /s/  Mark W. Begor
                                          ------------------------------------
                                          Name: Mark W. Begor
                                          Title: Executive Vice President and
                                                 Chief Financial Officer

ACKNOWLEDGED AND ACCEPTED:

NBC INTERNET, INC.

By:  /s/ John Harbottle
   ---------------------------
   Name: John Harbottle
   Title: EVP Finance & CFO

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                             ASSIGNMENT OF PROMISSORY NOTE

GE Investments Subsidiary, Inc. ("GE Sub") hereby assigns the promissory note
from National Broadcasting Company, Inc. ("NBC") in the principal amount of
$340,000,000, attached as Exhibit A hereto, to NBC Internet, Inc. (f/k/a
Xenon 2, Inc.), a Delaware corporation ("NBCi"), and NBCi hereby accepts this
promissory note from GE Sub, in accordance with Section 2.4 of the Agreement
and Plan of Contribution, Investment and Merger, dated as of May 9, 1999, as
amended and restated as of July 8, 1999, as amended, among NBC, GE Sub, NBCi,
Neon Media Corporation and Xoom.com, Inc. pursuant to which NBCi is selling,
and GE Sub is purchasing, shares of Class B common stock of NBCi.

Dated:  November 30, 1999

                                   GE INVESTMENTS SUBSIDIARY, INC.

                                   By: /s/ Robert E. Healing
                                       ----------------------------
                                       Name:  Robert E. Healing
                                       Title: Vice President

                                   NBC INTERNET, INC.

                                   By: /s/ John Harbottle
                                       ----------------------------
                                        Name: John Harbottle
                                        Title: EVP Finance & CFO

NBC hereby consents to the above-referenced assignment of the attached
promissory note by GE Sub to NBCi and agrees to issue a new note, in replacement
of such promissory note, in the name of NBCi.

Dated:  November 30, 1999          NATIONAL BROADCASTING COMPANY, INC.


                                   By: /s/ Mark W. Begor
                                       ----------------------------
                                       Name: Mark W. Begor
                                       Title: Executive Vice President