Just a month into its $100 million branding campaign, Yahoo (NSDQ: YHOO) is switching gears and handing the reins to Omnicom Group shop Goodby, Silverstein & Partners from the previous agency lead, WPP’s Ogilvy & Mather, AllThingsD’s Kara reports. San Francisco-based Goodby, most famous for its “Got Milk?” ads, comes in as the TV and out-of-home ads appear to be turning some consumers off. Market researcher YouGov told SAI last week that since running the spots, Yahoo has experienced the biggest buzz score drop it has taken all year.

While Goodby is at the head, O&M will move to a support role, with its focus resting on international marketing efforts, including all forthcoming brand launches in France, Taiwan, Hong Kong, Korea, Brazil and Indonesia, Yahoo Integrated Marketing and Brand Management SVP Penny Baldwin told AllThingsD. It wasn’t a total loss for WPP either, as O&M siblings Neo and Mindshare will continue to manage the media buying and planning operations.

Baldwin insisted that the decision should not be seen as a negative judgment against O&M, or that the campaign had started off on the wrong foot. Bringing in Goodby is part of a plan to “broaden” its outside marketing views. Still, Baldwin did cite Goodby’s proximity to Yahoo’s Sunnyvale headquarters are plus. The means if the buzz on Yahoo’s marketing effort doesn’t show some turnaround, Goodby account directors will likely hear about it face-to-face.

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