Young & Rubicam, New York, is expected to acquire Media Edge and its $330 million in AT&T media billings from N.W. Ayer & Partners. A deal has not been signed, but AT&T, the major client, decided on Y&R Monday, said sources close to AT&T and Ayer. Three AT&T agencies, Y&R, McCann-Erickson Worldwide and FCB/Leber Katz Partners (via its sister TN Media) made bids for Media Edge. Though Ayer holding company Adcom is the seller, AT&T had the biggest vote in the decision. The deal will give Y&R responsibility for two-thirds or more of AT&T's $660 million in U.S. media buying. Y&R will maintain Media Edge as a separate buying unit and Beth Gordon will stay on as managing director, a condition mandated by AT&T.