After Microsoft recently threatened Yahoo! with a 3-week ultimatum to “accept our offer or else” (the ‘or else’ being a hostile take-over), Yahoo! have responded with a bewidlering tactic to try and gain leverage in the bitter talks. For two weeks, Yahoo! will be implementing Google Adsense into Yahoo! search.

The move is said by a Yahoo! spokesman to be an attempt to “maximize stockholder value, including the exploration of potential commercial business arrangements”, and will apparently only affect around 3% of all Yahoo! search queries, and will not affect other affiliate properties under Yahoo’s wing.

What is key here, is that Yahoo! claim to have been in talks to roll-out some kind of European search advertising partnership with Google long before the buy-out offer was made my Microsoft, making this more about posturing than anything else, and it’s certain to hit a nerve with Steve Ballmer and co, who have released this statement..

“Any definitive agreement between Yahoo! and Google would consolidate over 90% of the search advertising market in Google’s hands. This would make the market far less competitive, in sharp contrast to our own proposal to acquire Yahoo! We will assess closely all of our options. Our proposal remains the only alternative put forward that offers Yahoo! shareholders full and fair value for their shares, gives every shareholder a vote on the future of the company, and enhances choice for content creators, advertisers, and consumers.”

..raising concerns over anti-competetive practices, which mirror the concerns over the proposed Microsoft/Yahoo! deal. Is anyone else spotting a little hypocracy here? Ballmer is said to be furious that his threats continue to go unheeded, and Yahoo! seems to be taking the whole thing in their stride, responding with ever more outlandish ways to say “raise your offer”.