Exhibit 10.4

PLEDGE AGREEMENT

(WebMediaBrands Inc.)

This PLEDGE AGREEMENT (as the same may from time to time be amended, restated or otherwise modified, this “Agreement”) is made as of the 29 ^th day of May, 2009, by WEBMEDIABRANDS INC., a Delaware corporation (“Borrower”), in favor of ALAN M. MECKLER, a New York resident (“Lender”).

1. Recitals .

Lender has made a loan (the “Loan”) to the Borrower and Mediabistro.com, Inc. as evidenced by a Promissory Note of even date herewith (the “Note”) from Borrower and Mediabistro.com, Inc. to Lender in the original principal amount of Seven Million One Hundred Ninety Seven Thousand One Hundred Forty Three and  ²¹ / 100 Dollars ($7,197,143.21).

Borrower deems it to be in its direct pecuniary and business interests that Borrower obtain the Loan from the Lender.

Borrower understands that the Lender is willing to make the Loan to Borrower only upon certain terms and conditions, one of which is that Borrower grant to Lender, a security interest in and an assignment of the Collateral, as hereinafter defined, and this Agreement is being executed and delivered in consideration of the Loan and for other valuable consideration.

2. Definitions . Except as specifically defined herein, (a) capitalized terms used herein that are defined in the Security Agreement shall have their respective meanings ascribed to them in the Security Agreement, and (b) unless otherwise defined in the Security Agreement, terms that are defined in the U.C.C. are used herein as so defined. As used in this Agreement, the following terms shall have the following meanings:

“Collateral” means, collectively, (a) the Pledged Securities and each addition, if any, thereto and each substitution, if any, therefor, in whole or in part, (b) the certificates representing the Pledged Securities, and (c) the dividends, cash, instruments and other property distributed in respect of and other proceeds of any of the foregoing.

“Event of Default” means an event or condition that constitutes an Event of Default, as defined in Section 7.1 hereof.

“Obligations” means, collectively, (a) all indebtedness and other obligations now owing or hereafter incurred by Borrower under the Note, and the other Loan Documents, and includes the principal of and interest on the Loan; (b) each renewal, extension, consolidation or refinancing of the Note, in whole or in part; (c) the Accommodation Fee and other all fees and other amounts payable to Lender pursuant to the Note or any other Loan Document; and (d) all Related Expenses.

“Pledged Securities” means, subject to Section 5 hereof, all of the shares of stock or other equity interest of each subsidiary of Borrower owned by Borrower, as listed on the attached Exhibit A , and all additional shares of stock or other equity interest of each subsidiary of Borrower owned by Borrower from time to time or acquired by Borrower in any manner.

“Security Agreement” means the Security Agreement of even date herewith from Borrower to Lender and granting the Lender a security interest in the Borrower’s existing or future personal property and other assets described therein.

3. Security Interest . Borrower hereby grants to Lender a security interest in and an assignment of the Collateral as security for the Obligations. For the better protection of Lender hereunder, Borrower has executed appropriate transfer powers, in the form of the attached Exhibit B , with respect to the Pledged Securities and, concurrently herewith, is depositing the Pledged Securities and the aforesaid transfer powers with Lender. Borrower authorizes Lender, at any time after the occurrence of an Event of Default, to transfer the Pledged Securities into the name of Lender or Lender’s nominee, but Lender shall be under no duty to do so. Notwithstanding any provision or inference herein or elsewhere to the contrary, Lender shall have no right to vote the Pledged Securities at any time unless and until there shall have occurred an Event of Default.

4. Representations and Warranties . Borrower hereby represents and warrants to Lender as follows:

4.1. Borrower is the legal record and beneficial owner of, and has good and marketable title to, the Pledged Securities, and the Pledged Securities are not subject to any pledge, lien, mortgage, hypothecation, security interest, charge, option, warrant or other encumbrance whatsoever, nor to any agreement purporting to grant to any third party a security interest in the property or assets of Borrower that would include such Pledged Securities, except the security interest created by this Agreement or otherwise securing only Lender and as otherwise specifically permitted by the Note.

4.2. All of the Pledged Securities have been duly authorized and validly issued, and are fully paid and non-assessable (except as such rights may arise under mandatory provisions of applicable statutory law that may not be waived or otherwise agreed and not as a result of any rights contained in any organizational document).

4.3. Borrower has full power, authority and legal right to pledge all of the Pledged Securities pursuant to the terms of this Agreement.

4.4. No consent, license, permit, approval or authorization, filing or declaration with any Governmental Authority, and no consent of any other Person, is required to be obtained by Borrower in connection with the pledge of the Pledged Securities hereunder, that has not been obtained or made, and is not in full force and effect.

4.5. The pledge, assignment and delivery of the Pledged Securities hereunder creates a valid first lien on, and a first perfected security interest in, the Pledged Securities and the

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proceeds thereof. Other than pursuant to this Agreement or as specifically permitted by the Note, Borrower has not granted any other liens on, or security interests in, the Pledged Securities.

4.6. The Pledged Securities constitute one hundred percent (100%) of the outstanding capital stock owned by Borrower of each other Subsidiary of Borrower.

4.7. Borrower fully anticipates that the Obligations will be repaid without the necessity of selling the Pledged Securities.

4.8. Borrower has received consideration that is the reasonable equivalent value of the obligations and liabilities that Borrower has incurred to Lender. Borrower is not insolvent, as defined in any applicable state or federal statute, nor will Borrower be rendered insolvent by the execution and delivery of this Agreement to Lender. Borrower is not engaged or about to engage in any business or transaction for which the assets retained by Borrower are or will be an unreasonably small amount of capital, taking into consideration the obligations to Lender incurred hereunder. Borrower does not intend to incur debts beyond Borrower’s ability to pay them as they mature.

4.9. If the Pledged Securities are “restricted securities” within the meaning of Rule 144, or any amendment thereof, promulgated under the Securities Act of 1933, as amended (the “Securities Act”), as determined by counsel for Borrower, Borrower further represents and warrants that, except as disclosed in writing to Lender, (a) Borrower has been the beneficial owner of the Pledged Securities since July 17, 2007, (b) the full purchase price or other consideration for the Pledged Securities has been paid, and (c) Borrower does not have a short position in or any put or other option to dispose of any securities of the same class as the Pledged Securities or any other securities convertible into securities of such class.

5. Foreign Subsidiaries . Notwithstanding anything in this Agreement to the contrary, Borrower shall not be required to pledge more than sixty-five percent (65%) of the total combined voting power of all classes of equity interests or stock of any Foreign Subsidiary.

6. Additional Covenants of Borrower .

6.1. Borrower covenants and agrees to defend the right, title and security interest of Lender in and to the Pledged Securities and the proceeds thereof, and to maintain and preserve the lien and security interest provided for by this Agreement against the claim and demands of all third parties, so long as this Agreement shall remain in effect.

6.2. Borrower covenants and agrees not to sell, assign, transfer, exchange or otherwise dispose of, or grant any option with respect to, or create, incur or permit to exist any pledge, lien, mortgage, hypothecation, security interest, charge, option or any other encumbrance with respect to any of the Pledged Securities, or any interest therein, or any proceeds thereof, except for the lien and security interest provided for by this Agreement and any security agreement securing only Lender.

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6.3. Borrower covenants and agrees (a) to cooperate, in good faith, with Lender and to do or cause to be done all such other acts as may be necessary to enforce the rights of Lender under this Agreement, (b) not to take any action, or to fail to take any action t