Warning: Contains spoilers
So I just saw Days of Future Past at the theater. The Riptide question is effectively answered, although he wasn't mentioned we can assume he was experimented on and killed by Trask just like Emma and Banshee. Also Trask was arrested for selling military secrets, something all the summaries left out.
However there are a few things I'm not 100% clear on.
1.) Angel and Azazel's deaths
So Trask killed mutants while experimenting on them for his Sentinel project, and kept autopsy files on them. Of the five First Class mutants to be killed before the events of the film (counting Riptide), the only two who we saw in the autopsy files were Azazel and Angel, the two who were said to be killed by Project Wideawake in a firefight a year after the events of First Class.
So what does their autopsy files mean? Did Trask experiment on them after Project Wideawake killed them? Or does this retcon The Bent Bullet and give a new fate for them, the same as Emma, Banshee, and Riptide?
2.) The new timeline
I'm sure this will be a huge topic of discussion once enough people see this. So when Mystique is convinced not to kill Trask and saves the president's life, that alters the future so the sentinel attack never happens, and Phoenix never awakens inside Jean since she and Scott are still alive.
So does this erase the events of all the movies except First Class and the present day events of Days of Future Past? Or do they still play out, just in a slightly different way?
Does X-Men Origins: Wolverine never happen? If so, that means Agent Zero would still be with Stryker wouldn't he, since Wolverine wouldn't have killed him. I think maybe since Wolverine would have no memory of the things his older self did while in his body, events could potentially still play out after Mystique saved him from drowning.
Do X-Men and X2 never take place, or do events play out in similar way? Obviously Jean isn't "killed" at the end of X2 this time, was this because the future was drastically altered or because Xavier saw events leading up to Jean's real death that time he read Wolverine's mind and took precautions to prevent Phoenix's awakening? What of Mystique? Does she fully turn back to the side of good (what with saving Wolverine from drowning and all), or does Magneto eventually convince her to go back to his side thus leading to the events with them, Toad, and Sabretooth in the first film? Does Senator Kelly still plan for the mutant registration thing or does he not do that since Mystique saved the president?
What of the events of X-Men: The Last Stand? This would be drastically different than before since Phoenix doesn't awaken, kill Cyclops and supposedly Xavier. Does Magneto still recruit members of the Brotherhood thus causing the battle to play out in a similar style as before, except Phoenix isn't there with Magneto and Jean is there to fight alongside the X-Men. So I guess Kid Omega, Arlight, and Psylocke are either killed another way or de-powered.
Finally, The Wolverine. Does it play out the same way as before, minus the whole "Jean's death" thing? Does Yukio still go to Wolverine at the X-Mansion for the whole Yashida thing since Wolverine and Yashida do go back a long way.
One more thing: Does the "old timeline" still exist (like in Star Trek, Zelda, and Dragonball Z) or was it completely erased to make way for the new timeline?