TrekMovie is stating that 1, Leonard Nimoy is returning to the film as Spock Prime. In fact, he’s already done filming his scenes. His time in the movie will be much less than that of the previous film.
2, Benedict Cumberbatch is playing Khan in the new film. This, too, is according to several sources. There’s a lot to play with if this is the case. Spock Prime knows what a problem Khan can be, so he could warn new Spock and Kirk of the superhuman’s danger. Also, if they are warned, the new duo could handle things much differently, to prevent problems. But judging from the previously leaked pictures, that’s not going to happen.
3, Klingons are in the move and they play a pivotal part. There were scenes shot in the previous movie with Klingons but were deleted (rightfully so; they looked horrid!). These scenes as DVD extras could be clues as to how they will be handled.
So that’s where Trek news currently stands. So we have possibilities, but no script specifics yet.
Source: SciFi Pulse