OK sorry if this has been discussed before, and it likely has... But in Trek XI a separate timeline or alternate reality is created when the Narada destroys the Kelvin and then ofcourse subsequent events with the destruction of Vulcan. But it really starts with the Kelvin destroyed. So Spock Prime can't travel forward in time back to the late 24th century because he would be returning to a future from the universe he is in. Just like Doc and Marty in Back to the Future Part II. OK I get that, can't go back to the future. But what about all the previous time travel stories that Trek has done. Kirk and Spock traveling back in 1986 to pick up two whales and causing the disturbances they did, however minor...when they returned to the 23rd century shouldn't it have been a different universe then from when they arrived? The original timeline didn't have a group of weirdos foolin' around San Franciso looking for whales, and the original timeline didn't have that scientist/tour guide Gillian suddenly go missing without a trace. Same applies to all the other time travel stories, how was it that the characters returned to the "prime" universe after meddling around in the past? But poor Spock gets stuck in the past of an alternate universe.
Technically, they did. Realistically, I feel it was a so-subtly altered 'verse, they couldn't notice. Personally, I don't cotton to the idea of a new reality, I think it's an altered timeline. But somewhere, there is a 'verse where Nero never did that s**t, so its timeline is intact. OR- is Trek 09 just a view of an alternate reality with an adjusted timeline???? My brain hurts now.
Watch the TNG 7th season episode "Parallels". Data has a pretty in-depth explanation about time lines, and how different ones can be created.
We cannot be sure any time travel actually occured in this movie. The rupture of the universal wall between realities may have simply thrown Spockprime into an alternate reality that had not advanced as quickly as his Prime universe.
Or, one that advanced faster! Or perhaps the non-linear tangental realities with a similar nominal coefficient simply bled into each other!...?
This is how I see things; everything that's happened in every series and every movie up til STXI is all part of the same prime universe, with all time travel a part of what shapes that universe. Like McCoy in COTEOF, Nero and the Narada is a random element going back in time and changing history, thereby creating another universe that takes a different, parallel direction to the prime universe. Big fan of Back to the Future, by the way.
I see Star Trek as needing a Crisis on Infinite Earths before to long. Of course I hope the third NUmovie deals with A Terran Empire invasion of NuTrek. Using the already weakened Universal boundries caused by PrimeSpocks misadventures the ISS Enterprise and a fleet comes looking to take over. Space battles galore!!