I just read this from Wikipedia.com
Spin-offs:
Lauren Donner, producer for the first two movies, has said the movie studio is interested in producing two spin-off films. One film will star Wolverine, in which
Hugh Jackman will reprise his role as the clawed warrior. Screenwriter
Sheldon Turner is currently working on bringing Magneto to the big screen in his own spin-off film. The plot will deal with the character's friendship turned sour with Charles Xavier. Turner has stated that "It's going to take place from 1939 Auschwitz up to 1955 or so." Although it at first appears unlikely that
Ian McKellen will reprise his role, recently he stated that he would actually be playing a younger incarnation of his character due to a CGI effect which is able to make him appear younger.
Rebecca Romijn, who plays Mystique in the X-Men franchise, has been approached about a Mystique film. Reputable movie news site
http://www.superherohype.com is now reporting that
X-Men: The Last Stand screenwriter
Zak Penn is now writing a third X-Men spin-off film as well.