I thought I read somewhere that they want to do a X-Men Origins: Storm movie.
Never heard about that one, but there is already a script for a Magneto origin film. As I understood they were just waiting to see how well Wolverine performed before moving ahead. The producers are also supposedly keen to do a film about the younger days of some of the popular X-Men while they were attending Xavier's school and learning about their powers. The Wolverine film certainly provided a door for that with the young Scott Summers and where his character went.
I also read this morning that they're moving ahead with a Deadpool spin off film for Ryan Reynolds.
I've heard multiple versions of the young X-men discussed. Right after X-3 it was thought that we would follow the younger group that survived that film (Rogue, Iceman, Kitty, etc), then there was talk of an entirely new group we hadn't seen yet, and lately Lauren Schuler Donner has been talking up younger versions of established characters in a film called X-Men: First Class or something along those lines.
Like I said in another thread, there are about half a dozen X-men related films in various states of rumour/development, so it will be interesting to see which ones actually make it to the screen.