Hilary Duff has signed on for a multi-episode arc on Gossip Girl, according to EW.com. Duff will play a character named Olivia Burke, a movie star who attends New York University in search of a traditional college experience. Blair (Leighton Meester), Dan (Penn Badgley) and Vanessa (Jessica Szohr) were also accepted to NYU, and Duff winds up [...]