I think it was very clearly stated in the film that this is an ALTERNATE UNIVERSE - they haven't wiped anything away. The "Prime" universe still exists, and only 2 things were changed in the "Prime" universe because of this movie:

1) Romulus has been destroyed
2) Spock is presumed dead (though he's actually in the "Alternate" universe)

If they want to, they can still make TNG-era and beyond stories set in the original universe because it was NOT destroyed - it still exists. There are just two different versions of how things went - the "Prime" universe, where Enterprise, TOS, TAS, TNG, DS9, and Voyager all took place, and the new "Alternate" universe, where the Abrams movie and any of its sequels will take place. (And I guess Enterprise still took place in this new universe, since it is set before 2233 ... )

And while Spock "Prime" told Alternate Kirk that he could under no circumstances tell Alternate Spock that he exists, he was just saying this so A-Kirk would let himself become friends with A-Spock instead of the two hating each other. The very fact that P-Spock spoke to A-Spock at the end of the film with no "universe-ending paradox" proves that this is a branching timeline, and the original was not destroyed. Hell, someone from after Romulus is destroyed could theoretically go back in time to when the Narada attacked the Kelvin and stop that from happening, thus destroying the "Alternate" universe and restoring the timeline to its original state.

But I doubt that'll ever happen, because that would truly invalidate the new universe the way people like Hunter claim the new universe invalidates the "Prime" universe (which it doesn't).

--edit--

Oh, and Skyjedi, I'm glad you were able to enjoy the new film despite your strong predisposition against it. I don't know what's up Hunter's ass, but it clearly wasn't up yours like I assumed it was :-)