1) The villian is Khan. The only thing that makes me doubt that is the end of the japanese trailer. when cumberbatch's character talks about doing anything for family. If he's mitchell then gary mitchell has radically changed from tos. 2) Alice eve is Carol Marcus. 3) I believe the last glimpse of the japanese trailer is a fake out. I believe that we might be seeing the severe injury or death of a star trek character happens here but I believe that in this case we will see spock being the one who is on the outside looking in and I believe that the character in danger is Pike.
Alice Eve's Elizabeth-Denner hairdo is as blatant a clue as the hand. But it can't be both Mitchell and Khan, so Abrams is frakking with us. Therefore it's Lord Garth, which is also the best physical match for Cumberbatch. I wonder if the hand is Uhura? I'm halfway expecting her to die and I went so far as to google up some pix Zoe Saldana's hands. No I'm not an obsessed fan no matter what that sounds like! She happens to have fairly large hands.
It was a gold command outfit and a white hand on one side and a blue science and a white hand on the other. It's not Uhura. I don't think it's Garth of Izar.
Alright, I want to make a theory too I think that Cumberbatch is one of the fellow Starfleet Officer, and Kirk's old friend. Then in the beginning of the movie, he is considered as MIA in a mission because of Kirk's fault. Later, Cumberbatch returns to Earth with superhuman power and become a terrorist, Kirk and the Enterprise is called back to handle this rogue officer (just because Kirk knows him better than anyone else) Maybe he is a victim of Starfleet / Section 31 secret experiment of Enhanced Human, I don't know. But Cumberbatch is return as a superman. Well, I don't care if he's Khan, Garth, or Mitchel, because I'm not following TOS. So basically I don't know them and don't have any attachment to any of them. And Khan, well yes, I watched the Wrath of Khan, but I don't mind if they remake him in this new movie.
The only effect that killing off a significant character would have on me (and many other fans I'm sure) is that I would be angered to the point that I would lose interest in this "new" franchise. This franchise was just succesfully rebooted, and with such a young crew the future possibilities are endless. None of the main characters have to die to make this movie epic. Honestly, all this talk of Khan, and another death scene maybe even Spock, is ridiculous! I can only hope that JJ Abrams is more original than that or I'm really going to be disappointed...and I'm pretty sure I won't be alone. Wow, another death scene... please, spare me!
I've updated my theory. I no longer believe that it is khan. The opening as described virtually excludes him. What if Soran is trying to gain technology throughout the alpha quadrant to go after the borg who killed his family.