Guys, the number one rule of Star Trek fandom is, don't try to make sense of time travel physics.
This. Going by "Time Squared", Spock, Nero and their ships should have faded away once they started making changes.
It's pretty clear from the context of the movie that in the Abramsverse, nothing exists from the original timeline except for Spock.
Eh, Admiral Marcus' desk was packed with references to pre-TOS happenings:
-Aries IV from VOY: "One Small Step"
-The Phoenix from ST:FC
-The Ringship Enterprise from ENT and TMP background art
-NX-Alpha from ENT: "First Flight"
-Enterprise NX-01 from the ENT TV series.
I say they were no accident, but confirmation of Bob Orci's statements about a branching timeline with an unchanged pre-2233 past.
Plus, they bent over backwards to explain how and why Khan was awoken years before "Space Seed", and there was even a deleted scene where Carol explains why she has a British accent in this timeline.