SG Cowen downgraded Yahoo! (YHOO

) to sell from neutral.

Analyst Scott Reamer says Q1 revenues and EPS are a huge miss, and he cut the $0.07 2001 EPS estimate to a $0.26 loss.

He says the new CEO search and the $500M stock buyback will not address near-term issues. He says at a 20%-30% EBITDA growth rate, the media company valuation nets $6 billion in company and $10 in stock. Reamer thinks some investors and Yahoo ! are underestimating the problem in Internet advertising: too much bad inventory.

He believes any media company contemplating a Yahoo takeover

needs to think about the "poison pill" the company adopted on March 1 and the real operating and management challenges Yahoo! faces, both which make a takeover less likely and don't necessarily establish a floor above his $10 target.