Deadpool will be in the X-Men Universe

Nearly 8 years after his first appearance in X-Men Origins: Wolverine, Deadpool will have his own movie. Fans speculated wether it would be standalone (much like theories on the Dr. Strange adaptation) or if he would remain linked to X-Men. Writer/producer Simon Kinburg confirmed in an interview with ComicBookMovie.com that, yes, Deadpool will be in the X-Men Universe:

"There’s definitely a sort of overall plan that we’ve all been talking about for the X-Men universe now, and Deadpool obviously fits into that... So yeah, I guess I would say it's part of certainly an overall timeline and thought process that goes into these films, some of which is inspired by the comics and some which is inspired by seeing what Marvel’s done with telling a larger tapestry and linking all those movies together, even as they stand independently as well. The same kind of thought is going to go into these X-Men movies at Fox."

Kinburg confirmed a day later to CinemaBlend, the addition of Deadpool to the X-Men universe. He also commented that the X-Men: Apocalypse and future Fox comic book movies would stick to a similar structure to that of Marvel's cinematic universe, in that; "[The Movies] all feed into one another in the sense of wanting to tell this sort of massive story that can take place over multiple movies." With X-Men: Days of Future Past setting up a completely rebooted story line, Fox will have a blank canvas with which to work. The Deadpool movie is set to drop on February 2, 2016, with X-Men: Apocalypse coming a few months later on May 27th.