"I think it was the scent that did it," reports People page editor Belinda Luscombe." A cultural milestone of sorts was reached this week with the announcement that "The Bridges of Madison County" has fallen off the New York Times bestseller list, ending a 162-week run during which the book sold 10 million copies. "Bridges" first hit the list in August 1992, and has stayed there longer than any fiction book since "The Robe" captivated readers in the 1950's for 178 straight weeks. "People got the book, the movie, the calendar, the follow-up books, the record," says Luscombe. "But when they released the scent, people realized this whole thing was just a tired marketing ploy and they lost interest. Either that, or everyone in America already has a copy and there's simply no one left to buy it."