I saw a screening of "The Wolverine" tonight and stayed for the mid-credits stinger, the brief clip that essentially serves as a cute prequel to Bryan Singer's "X-Men: Days of Future Past". Turns out, the reports are true.
No doubt a pirated form will end up online this weekend sometime, but if you want the full details now then read on.
Two years after the events in "The Wolverine", Logan is walking through an airport waiting in line for the metal detector. A Trask Industries promo (can't recall if it's either a news report or commercial) is playing on the TV screens in the airport.
Just as he gets to the detector, coins and other metal bits around him start levitating. He realizes someone is behind him and spins around. A man in a black trench and hat slowly lifts his head - it's Ian McKellen as Magneto. A Magneto who seems to have his power back.
Magneto then tells him that something is coming that could destroy all mutant kind and wants him to join the fight. Logan turns him down, saying why should he join him. It's then he realises all the noise and people around him have stopped moving.
Patrick Stewart's Professor X in his wheelchair rolls through the airport around the frozen people and up to Logan. A disbelieving Logan asks him "how is this possible?". Xavier replies with a reference back to the first film - "Like I told you before, you're not the only one with gifts". Cut to black.