Rumors are starting to circulate that Bryan Singer might direct a possible 4th installment to the X-Men film franchise.

Read articles here:
http://www.cinemablend.com/new/Bryan-Singe...X-Men-3846.html
http://www.httwww.cinematical.com/2006/11/...direct-x-men-4/

A New (cloned) body for Prof. X is a possibility. Apocalypse would be an interesting villain to consider. They have already introduced Angel. So an Archangel wouldn't be so far-fetched.

another intresting big bad would be the Hellfire club with Emma frost and Sage defecting in the middle of the movie.