geekgasms -- I love it. I was having multiples in the Kobyashi simulator scene -- Chris Pine was so funny I was actually high. That scene'd be funny to anybody, but to a hardcore trekkie ... we all know the story from Wrath of Khan but to see it with your own eyes, I was in geek heaven.
I thought Nero was a weak villain. I could accept him more if he wasn't Romulan, but Romulans don't act like that. Why blame Ambassador Spock? The Romulans know Spock from reunification. It's like Russia blaming Ghandi for Chernobyl--makes no sense. And Romulans don't commit genocide. They're vicious and aggressive, but they do have some class. In Nemesis, Shinzon went too far and the Romulan fleet turned against him. Nero is just a petty, vengeful idiot, and I can't see him rising to command a Romulan starship.
Spock has had his troubles with command, but not out of wimpery. He has trouble commanding illogical humans and he doesn't like to fire weapons, but Spock wouldn't decide 'let's sit around waiting for orders from Starfleet' while this nut Nero runs off to target Earth with Red Matter. They could have done Spock a little better justice, not such a washout as captain.
Most of the canon glitches had a payoff -- like it's clear from 'Khan' that Spock didn't program the Kobyashi simulation -- but it's worth a little discontinuity to get that showdown between Spock and Kirk.
Anyway, those are just tidbits. I was in geek heaven from start to end. Most of all, I'm happily surprised at how damn excellent it was. It's a good day to be hardcore.