Trailer seemed more like a Transformers movie then a Trek one, but I will reserve judgement until I see the full movie itself. Have to say I'm pretty excited.
As for the villain, I'm thinking Garth might be a good bet. I mean, we're not seeing the freaky silver eyes and super-powers that Gary had, unless the story is that Gary never goes through the barrier and something else makes him crazy. I'm not thinking Khan, that seems a little too obvious.
Though it's hard to make accurate guesses based on a trailer that is mostly explosions and people looking shocked.