Taylor Swift has never been shy about sharing her emotions through music. John Mayer, for example, recently kvetched to Rolling Stone that Swift's confessional ditty "Dear John," which is widely assumed to be about him, "was a really lousy thing for her to do." But, as the 22-year-old explains in the November issue of Glamour, she never reveals who her songs are about. "How presumptuous!" she exclaims after learning of his comments.