(Some spoilers...)
I really liked it but it had its flaws. It was too short. Some of the interactions and backstory could have been expanded. What the hell was up with that thing with Uruha and Spock?
Also, cliches. How many times are we going to see black holes used as time travel? The red shirt thing was pretty stupid, actually.
Hell, cameos and old school lines getting repeated is cliche now, since every movie is a remake of something 20 years ago. (Star Trek, Transformers, GI Joe, etc., etc., etc.) Ha ha, Bones said a "Dammit I'm a doctor" line. Very funny, except I was expecting that, so it wasn't funny. It's almost like they need to get that out of their system so that they can move on to the actual plot.
Overall, the characters were good, and it was the best part of the movie. Karl Urban actually pulled out a convincing Bones. Kirk seemed like a brash and brazen character, like bovine said. Spock was really good, too.
But, the movie was good like Transformers was good: yes, the movie is worth watching, but it's still a fucking Michael Bay film.
Rosalina: But you didn't.
Robert: But I DON'T.
Rosalina: You sure that's right?
Robert: I was going to HAVE told you they'd come?
Rosalina: No.
Robert: The subjunctive?
Rosalina: That's not the subjunctive.
Robert: I don't think the syntax has been invented yet.
Rosalina: It would have had to have had been.
Robert: Had to have...had...been? That can't be right.