From what I can tell, being a non-comic reader; Wolverine comes back from a bad, Sentinel-overrun future to try and persuade Young Charles and Young Magneto to do - something - that will make sure there's no bad, Sentinel-overrun future for him to come back from. Featuring all your favourite mutants from both ends of the franchise, ie Patrick Stewart et al AND The Guy Who Is Young Charles et al. And Wolverine. Buzz is good but I don't think anyone, including press, has seen the whole thing yet.