For a second there I thought, "OMG! Pedo!" Then I realised that Jennifer Lawrence was Raven/Mystique in X-Men: Origins. I don't know about her looking plain, but she definitely looked young; I didn't recognise her and thought she was some new sixteen year old actress
Also, how is it that everyone else knows about all these 'young adult' titles that are so popular these days and yet I never find out about them until a movie comes out and gets talked about here? Anyway, all the other YA movies-based-on-best-selling-books that have come out in the last few years have completely sucked, primarily because the source-material was so lame; this one actually looks like it might be pretty decent.