http://splashpage.mtv.com/2013/02/15...f-future-past/

"This movie's gonna be not only quite epic, 'Days of Future Past,' but it also takes place in completely different times than the 'X Men' movies have taken place," he said. "There'll be new technology, new things we haven't seen before in 'X-Men' films. Certain characters and certain story and certain drama that hasn't be done yet, so it's not so much sequel. It's more of its own kinda thing."
http://www.ign.com/articles/2013/02/...men-last-stand

There are science fiction aspects of the movie, and then thereís some retro science fiction that the X-Men films havenít had quite yet. So weíre exploring that, which will be fun. And thereís an attitude [difference]. We discover our characters, particularly the younger characters, at a different place in their lives. Every character you discover in this movie is in a completely different place than youíve ever seen, emotionally, and it's about them moving through that.
Jackman, Paquin, Page, and Ashmore are all returning as well. Singer has been sending mixed signals too about how much he's going to keep to the continuity of the first three films. He's said he won't ignore the events of X3, but that he will be in a position to "repair" a few things.

Just the fact that he's said we're going to see new things and technologies that we haven't seen in X-men movies before, though, has me extremely excited.