WARNING SPOILERS

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SPOILERS ABOUT THE JJ STAR TREK:
Nero is determined to destroy all planets in the federation.
Nero wait 25 years for old spock after Spock's ship time jumps from the kelvin event. Nero capture old Spock's ship which in turn gave them the technology needed to destroy planets.
Nero drills a hole into the planet's core and then deposits red matter that creates a singularity from within the planet itself.
Spock's mother, "Amanda" dies. the ground gives way under Amanda and they are unable to keep the transporter lock.
Vulcan is destroyed.
Pike is tortured by Nero, but is not killed.
Kirk is not really captain.
Spock displays a lot of emotion.
In the End, Spock launches an assault in old Spock's ship, and releases the red matter into the ship causing a singularity to form. Then Kirk blasts the hell out of it after Nero refuses to surrender.
Spock meets old Spock at the end of the movie. Spock wants to leave Starfleet to help rebuild the Vulcan culture, but old Spock talks him out of it as he himself will carry the knowledge to a new colony of Vulcans.
old Spock stays in the 23rd century.
No old kirk in the film.

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WARNING SPOILERS