Yahoo! sent out a newsletter this month notifying customers that U.S. Sponsored Search Listings No Longer on MSN. And I quote,
MSN's U.S. search distribution agreement with Yahoo! Search Marketing ends this month, and Yahoo! Sponsored Search listings will no longer appear in MSN's U.S. search results. Although we regret the loss of MSN as a distribution partner, it was not unexpected, and we do not anticipate a significant change in the total amount of traffic to our advertisers as a result.
We expect that MSN will continue to display Yahoo! Search Marketing Content Match listings in the U.S., and Sponsored Search listings in non-U.S. markets, beyond June 2006.
As you know, MSN has been powering the sponsored search side of MSN Search and Windows Live Search with Microsoft adCenter. So, is this the official end of the Yahoo! & MSN relationship. Looks that way.
Forum discussion at WebmasterWorld.