Omnicom to move to lower Manhattan?

The New York Post says this morning that Omnicom Group is mulling whether to move downtown to 100 Church Street, an area so far south when it comes to the ad industry's favored locales that it would give new meaning to the word "downtown." (Anyone remember when it was big news that Ammirati & Puris was moving to the East 20s?) The story, which erroneously refers to Omnicom as an advertising agency—it is a multinational, omnipresent, communications conglomerate, dammit!—also says that "some prospective tenants have turned up their noses at the renovated Church Street lobby and its Swarovski crystal chandelier." While there are few specifics as to which of Omnicom's properties would move into the new space, if it includes the Omnicom/DDB Worldwide headquarters at 437 Madison Avenue, that would be yet one more defection from the increasingly ad agency-free Madison Avenue. If I'm not mistaken, the ad industry's "Walk of Ad Icons"—or whatever it's called—is embedded into the sidewalk in front of 437 Madison, isn't it?