- Mike Shields, Mediaweek

NEW YORK Instant messaging platform Meebo has begun selling its proprietary ad placements across a network of 40 different Web sites reaching over 45 million unique monthly users.

Meebo.com synchronizes multiple social and instant messaging platforms -- including AOL Instant Messenger, MSN Messenger, Facebook and others -- in a single Web browser interface, enabling seamless chat between multiple circles for friends.

The company has developed a signature "brand showcase" ad unit, or MediaBar, which expands into an oversized 900 x 400 banner that officials claim has proven highly successful for several brand advertisers. According to Meebo executives, the showcase unit regularly drives click-through rates in the neighborhood of 1 percent. Plus, 10 percent of those who do interact with these showcase ads share the ads with friends via Meebo.com.

Partners that have agreed to begin running Meebo's ad units in the second quarter of this year include Current TV, IGN.com, StarPulse, AddictingGames and Sugar Publishing. The idea is to build a network of social networking and communications platforms that can rival the reach of the MySpaces and Facebooks of the world and will also appeal to brand advertisers. "The result is increased scale for social campaigns," said Meebo chief revenue officer Carter Brokaw.

Meebo executives are scheduled to present details on the new expansion at the iMedia Breakthrough Summit event on Mar. 23 in Coconut Point, Fla.