AK: It's funny you ask about time travel and the idea that time sorts itself out. There was a line that we had written that was shot which ended up getting cut from the movie. Watching it the other day, I wish we'd kept. When Kirk and Spock Prime are in the cave and Spock's telling him everything, there's a mention by Kirk of "How is it that I found you in this cave in the middle of an ice planet? It's insane that we should ever even meet this way." Spock says, "Perhaps it's the timestream's way of trying to mend itself. It is fate and destiny trying to bring us together."
RO: We're using the rules of quantum mechanics for time travel on this one, as opposed to the classical Einsteinian rules of relativity. One of the subsets of that theory is that there are multiple universes and that the things that are most probable to happen, happen most often in more universes... So there's more universes out there where Kirk and Spock get together and hang out than not, just because that's what quantum mechanics would say. We were very much playing as much as we could with the latest theories, and trying to tie those into a real sense of destiny. The movie does rely, to some extent for the fans, on a real knowledge of the fact that everyone is going to end up in their proper place.