Orci said that the alternate reality used in this movie is a departure from all the other time-travel rationales in previous Trek.
I don't consider this a big deal. I just think of it this way:
It's the black hole. That alone makes this different from any previously seen method of Trek time travel.
Assuming that this is not just an alternate timeline, but an alternate *universe*, that the Narada
and the Jellyfish
both crossed into. (It would certainly explain a few things, such as the look of the Kelvin
, the differing stardate system, etc.)
Thus, the prime timeline we all know and love is doubly protected.
That's how I view it, too. The black hole aspect is definitely the variable that makes it all seem plausible to me.
As to alternate timelines as a result of time travel... My username comes from a character who soley exists in a different timeline because the past was messed with. In this timeline, Spock died as a boy and as a result never became Kirk's First Officer. So, to those who say that time travel doesn't create alternate timelines or whatever in Star Trek, I disagree.
I, personally, think that you can't change the past. So, if you were to time travel and kill a person, it won't matter because it was going to happen that way anyway. If I was doing the writing, that's how I'd make it. But, fortunately, or unfortunately depending on how you look at it, ST doesn't work that way.