Reports from ComicBookMovie show that while Hugh Jackman hasn’t officially been signed on to be in Days of Future Past, he is in talks. This makes me wonder why he’s ‘still in talks’ while McKellen and Stewart are already signed in. Could it be that this role is going to be more than a walk-on cameo and therefore they need to work out pay, schedule, etc? This would lead creadence to my thoughts that Wolverine may be the time traveler instead of the Kitty Pryde.
Apparently he ‘hasn’t read the script’ yet according to this article noting that the man is getting a Star on the Hollywood Walk of Fame (go Hugh!). If it’s just a cameo, would he really need to know that much about the script? Did he bother to read all of First Class or did Vaughn just tell him “Okay, so, Xavier and Magneto are out recruiting mutants, I have an idea for a scene where they walk up to you, try to introduce themselves, you tell them to f-off, it’ll be hillarious”.
UPDATE: here is a video of him saying to MTV that he hasn’t read the script yet and he is a bit cagey which means to me that there is likely more than just a cameo going on
X-Men: The (fan fic) Series 