What is that movie coming out about destiny?

I think it was during the previews before Inception in which I saw a movie coming out which basically was about this guy who had found out about the inner workings of reality. He found out everyones destiny was predetermined and that he wasn't supposed to meet a certain girl he met. The premise is he tries to chase after this girl instead of follow he supposed destiny. Does anyone know what this upcoming movie is and when its coming out?