Must say, mixed feelings. In many way it reminded me of Bayformers - a good action/sci-fi with Trek elements. Difference between this and Bayformers is, Trek elements were much more prominent. Still, there are some things that drag the experience down.
Good points:
-Kirk. Whoever that bloke is, he's perfect for the role of the smirking, daredevil but also intelligent captain (cadet, actually). Very good acting, and I did not miss Shatner's "Bring... this... ship...around..." plodding speech pattern.
-McCoy: Again, spot on actor and character moments ("Damn it, I'm a doctor, not a physicist!") and apparently he's also afraid of being in space, not just of transporters. Sadly he is mostly absent in the second half of the movie.
-Uhura - she's very much like a younger Nichols. However, her character is... see below.
-CGI: Is breathtaking. You gotta wonder how First Contact or Resurrection looked like if they had a budget like this. From Vulcan landscape and cities to the various starships, is really cool looking.
-Continuity: In an incredibly clever and unforseen plot twist (I bet this was the third writer's work, not Orci's) the whole movie becomes pretty much an alternate universe, due to the time-travel of an older Spock back to the begginnings of Kirk's life. So, the Trek we know still exists in some paralell universe, and this new movie is in another reality with a more emotional Spock, more responsible Kirk and well, without the planet Vulcan.
-Nimoy: He still RULES. And he has a pretty large role, not just a cameo. And, has some pretty funny moments. "I'd say, live long and prosper (to young Spock) but that'd seem selfish. So, prosper!")
-Captain Pike: It was a really nerdish moment to see him appear, and surprisingly he's not a hi-then-die character but survives to become an Admiral (in his trademark wheelchair, though I miss the funny blinking light).
-Little things like remembering Vulcans have green blood and are much stronger then humans, keeping the old uniforms almost intact.
Bad things:
-Plot. It's... shallow, sometimes takes leaps of logic so huge Unicron would fall through it, and the general story arc is very little. After spending half an hour on the mandatory character development, we are thrust into the thick of the action where lots of silly things happen just to make the story progress, such as Pike making Kirk from cadet to Number One on the spot (certainly there were more experienced officiers on board), Spock launching Kirk in an escape pod to an unhospitable planet for mutiny (erm, that's what the brig is for) just so that Kirk could meet older Spock and also have a mandatory "big scary alien chase" scene. (the beast is btw totally ripped of D&D's Etheral Marauder).
But the biggest issue is when Scotty manages to transport themselves aboard the Enterprise from LIGHTYEARS away! 'cause otherwise, you know, there was no way Kirk could get on the ship on time for the plot to progress.
-Nero (Eric Bana) and his ship. Well, after Gul Dukat, Khan or the Borg, one of the most shallow Trek villains of all time. Not to mention that he's romulan, which the writers felt the need to mention 10 times during the movie, mostly because he and his crew looks nothing like romulans (with beards, tatoos and bald heads) - not to mention I find it unlikely romulans would work as miners. They would find that work demeaning.
His ship is the most horrid thing ever seen in Trek, adorned with totally non-functional spikes to make it scary (see a pattern here? Megatron and the Cons got this treatment from Orci too). Also, being the size of a station, the ship still has no shield and is easily disabled by ramming another ship into it (happens twice in the movie). Not to mention, overpowered - I find it hard to believe that a romulan mining ship that is (judging by future Spock's age) around 10-20 years after Voyager's time, could destroy 27 klingon ships, the whole earth and vulcan fleet...
-Spock. Although he is well-written as a character, unfortunately Quinto just doesn't "sells" as a vulcan. I have seen background Trek Vulcans look more convincing in this outfit and prostethic ears. It doesn't help that he is constantly 'almost' smiling, which would make sense in the second half of the movie where he embraces his human half, but he does it in the first half too. In certain scenes, he is almost 'Sylar-creepy".... and the real Spock simply makes him fade in comparison when they are on screen together.
-Uhura: Apparently her character developement means that she flirts with Kirk and kisses Spock a lot. (yes, Spock, you heard me right).
-Scotty: never seen Simon Pegg before, but sadly he not only doesn't resemble Scotty much, the character is also totally unlike Scotty. Maybe i natural english his accent could make it work.
-Chekov: Man, he was annoying. The new Wesley Crusher... at least they could have found someone who looks a bit like Walter Koening. And - not sure how the english version is - but the hungarian dub so much overdid his russian accent that the whole theater was laughing every time he spoke.
-Zulu: Not having trouble with the character (they even got his fencing skills to play out) but just didn't like the actor.
-Aliens... or rather the lack of regular Trek aliens. For some strange reason we see no Andorians, Tellarites or Bolians, old federation races - but the writers put in a lot of weird new races which look more suited to Star Wars then the mostly humanoid Trek races. Also (sorry for being a nerd) there is an Orion girl in Starfleet although the orions did not join the federation yet at this time (or even later, come to think of it).
-Shaky Baycam. It strikes again, even though Bay is not affiliated with the movie.
-Some minor things: phasers now fire bursts, not rays. Torpedoes can now be shot down, apparenty Earth or Vulcan has no means of orbital defenses other then their fleets, and a borer that can bore to the core of a planet needs to be lowered into the atmosphere on a huge chain, not fired from the ship, 'cause it looks cool. Also, everyone seems to be aware that the Romulans are the same race as the Vulcans, even before history is altered by time-travel.
-And, you can create black holes with tomatoe sauce.

All in all - an entertaining movie for all audiences, but from a Trekkie point of view, it's not the holy grail. Far from it.
Still, if this movie spawns a new series, I'll be very, very happy.