Still harboring fantasies about settling down with Uncle Jesse in a beautiful San Francisco Victorian and trading zingers with Bob Saget and the Olsen twins? Then we have bad news. E! Online reports John Stamos is inching toward the altar with longtime love Leah Marsh, a Pilates and yoga entrepreneur. Seems the low-key couple of three years is now cohabiting, with a source pronouncing, "It really is that serious." Alas, Leah Marsh-Stamos just doesn't have the same ring as Rebecca Romijn-Stamos.