Best friends, boyfriends, high school and haute couture -- Gossip Girl has gone from a guilty pleasure to becoming the show everyone is talking about, from Rolling Stone to Vanity Fair, from gossip columnists to President Obama. From its not-so-humble beginnings as a bestselling book series set in the posh Upper East Side private schools of New York City, this show the Boston Herald deemed "every parent's nightmare" has catapulted into the pop culture...