AMENDMENT NO. 1 TO CREDIT AGREEMENT

Exhibit 10.13

AMENDMENT NO. 1 TO CREDIT AGREEMENT

AMENDMENT NO. 1 TO CREDIT AGREEMENT, dated as of July 9, 2008 (this “Amendment”), among BT TRIPLE CROWN MERGER CO., INC., a Delaware corporation (“Merger Sub”), CITIBANK, N.A., as Administrative Agent, Swing Line Lender and L/C Issuer, and each lender from time to time party hereto (collectively, the “Lenders” and individually, a “Lender”).

PRELIMINARY STATEMENTS

Merger Sub, each lender from time to time party thereto (the “Lenders”) and the Administrative Agent have entered into a Credit Agreement, dated as of May 13, 2008 (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”).

Merger Sub has requested that the Lenders agree to amend certain provisions of the Credit Agreement as set forth herein.

The Required Lenders are willing so to amend the Credit Agreement pursuant to the terms and subject to the conditions set forth herein.

In consideration of the mutual covenants and agreements herein contained, the parties hereto covenant and agree as follows:

SECTION 1. Definitions. Capitalized terms not otherwise defined in this Amendment have the same meanings as specified in the Credit Agreement.

SECTION 2. Amendment to Section 1.01. Section 1.01 of the Credit Agreement is hereby amended as follows:

(a) by adding in the appropriate alphabetical order the following new definitions:

“Hedge Bank” means any Person that is an Agent, a Lender, or an Affiliate of any of the foregoing at the time it enters into a Secured Hedge Agreement, in its capacity as a party thereto, whether or not such Person subsequently ceases to be an Agent, a Lender or an Affiliate of any of the foregoing.

“Hedging Obligations” means obligations of the Parent Borrower or any Subsidiary arising under any Secured Hedge Agreement.

SECTION 3. Amendment to Section 7.03. Section 7.03 of the Credit Agreement is hereby amended by deleting the words in the third to last paragraph “ the first paragraph of this Section and”.

SECTION 4. Amendment to Schedule 1.01E. Schedule 1.01E of the Credit Agreement is hereby amended by inserting the words “except in the case of NBC Universal, Inc., which shall be limited to any Subsidiary of the foregoing (and shall expressly not include GE Capital or any other Subsidiary or division of General Electric Co. engaged in the business of corporate finance)” immediately after “any Affiliate of the foregoing.”

SECTION 5. Conditions to Effectiveness. This Amendment shall become effective upon the Administrative Agent’s receipt of executed counterparts of this Amendment, executed by Merger Sub and the Required Lenders.

SECTION 6. Credit Agreement. Except as expressly set forth herein, this Amendment shall not by implication or otherwise limit, impair, constitute a waiver of, or otherwise affect the rights and remedies of the Lenders, the Agents, the L/C Issuer, the Borrowers or any other Loan Party under the Credit Agreement or any other Loan Document, and shall not alter, modify, amend or in any way affect any of the terms, conditions, obligations, covenants or agreements contained in the Credit Agreement or any other Loan Document, all of which are ratified and affirmed in all respects and shall continue in full force and effect. Nothing herein shall be deemed to entitle the Borrowers to any future consent to, or waiver, amendment, modification or other change of, any of the terms, conditions, obligations, covenants or agreements contained in the Credit Agreement or any other Loan Document in similar or different circumstances.

SECTION 7. Applicable Law; Waiver of Jury Trial.

(A) THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK (EXCEPT AS OTHERWISE EXPRESSLY PROVIDED THEREIN).

(B) EACH PARTY HERETO AGREES AS SET FORTH IN SECTION 9.10 OF THE CREDIT AGREEMENT AS IF SUCH SECTION WERE SET FORTH IN FULL HEREIN.

SECTION 8. Counterparts. This Amendment may be executed in one or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. Delivery by facsimile or electronic transmission of an executed counterpart of a signature page to this Amendment shall be effective as delivery of an original executed counterpart of this Amendment. The Agents may also require that any such documents and signatures delivered by facsimile or electronic transmission be confirmed by a manually signed original thereof; provided that the failure to request or deliver the same shall not limit the effectiveness of any document or signature delivered by facsimile or electronic transmission.

SECTION 9. Headings. The Section headings used herein are for convenience of reference only, are not part of this Amendment and shall not affect the construction of, or be taken into consideration in interpreting, this Amendment

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SECTION 10. Severability. If any provision of this Amendment is held to be illegal, invalid or unenforceable, the legality, validity and enforceability of the remaining provisions of this Amendment shall not be affected or impaired thereby and the intent of such illegal, invalid or unenforceable provision shall be followed as closely as legally possible. The invalidity of a provision in a particular jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction.

[Signature pages follow.]

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed by their respective authorized officers as of the day and year first written above.

[Signature Page - Amendment No. 1]

[Signature Page - Amendment No. 1]

[Signature Page - Amendment No. 1]

[Signature Page - Amendment No. 1]

[Signature Page - Amendment No. 1]

[Signature Page - Amendment No. 1]

[Signature Page - Amendment No. 1]