Ok, if we're open to the possibility of time travel featuring in this story line too then I have a theory who it might be. Assuming they weren't lying and it is a character from canon then I would like to draw your attention to a very odd choice of characters who is definitely being included, Carol Marcus. She's being shown at an early age, presumably to have the relationship with Kirk that is mentioned in ST2. Now who in that film might have a genuine bone to pick with Starfleet? Not Khan, he was obsessed with Kirk... against all reason really. What kind of makes sense is that John Harrison is from the future and is actually David, Kirk's own son. We're meant to have a movie showing Kirk leading his crew into danger and lacking humility which fits nicely. David could easily blame Starfleet for what happened in ST2, and did so in the film. He could easily replicate the augmentation that Khan had and Genesis research could also offer a way to travel back in time, possibly even rejuvenate his cells in a manner of his choosing, maybe allowing for enhanced abilities. Maybe his intention is to prevent the disaster of the Genesis technology falling into Klingon hands as it nearly did in ST3 which could have had massive repercussions. If he's dealing with Kirk, and the fact that he is means he clearly wanted to for some reason, then a false name would be essential to the plot... Well the theory fits all the facts we know... I guess we'll find out soon enough. Anyone else think it's going to be a huge disappointment?