I first read about this film on the amazing Geek Tyrant website. The writers are Matthew Vaughn and Jane Goldman who both wrote the script for Kick-Ass. They are currently working on the script for the upcoming X-Men prequel movie X-Men: First Class but when Vaughn saw Inception he said he had to throw out 12 pages of the script because the Inception no-gravity fight scene resembled a fight scene in his script.
“…the jettisoned sequence was a sort of dream-space combat…the filmmaker said for the film the fight involving Professor X (James McAvoy) and some other mutants was to going to be presented with spinning rooms and other physics-bending imagery — visions that he felt drifted too close to signature moments in Inception.”
IMDB says the release date is June 3, 2011 which I highly doubt since the script isn’t even done yet or the movie fully casted. I’ll keep you posted when I hear about more X-men news.