Well, it was very good indeed. Star Trek (no handy subtitle to distinguish it from other Trek offerings) was a classy, well-executed reboot of the Star Trek saga, tossing away nothing and yet starting fresh - a neat trick if you can do it.
Here's a completely superficial look at the premise of the film: there's a time travel thing, and a Romulan attacks a starship. Jim Kirk is born, has a wild youth and is recruited to the academy. The Romulan attacks again, and Kirk ends up on the brand new starship Enterprise. He finishes meeting the other main characters, except for Scotty whom he then meets elsewhere. They save the day, but a rather big thing has already happened that will probably shock most Star Trek fans.
The casting was pretty much spot on, although I have minor reservations about Simon Pegg as Scotty. His performance was fine, and he looked very different from his guest role in Doctor Who (the Editor in "The Long Game"), but he didn't quite manage to look like he could be young Montgomery Scott. (He did well vocally, though.) Zachary Quinto (Sylar on Heroes) is visually perfect as young Spock, although I'm not sure he quite manages to give the challenging role enough gravitas. (There are also at least two scenes in which Spock goes well outside his old parameters, which will raise more than a few eyebrows.) Chris Pine as Kirk and Karl Urban as McCoy are particularly good. Pat, you'd appreciate how well Urban captures De Kelley's spirit for the role. Pine is not much like William Shatner, and yet he's very Jim Kirk. This Uhura is smart and sexy, Sulu gets to swordfight, and Chekov is a young techno geek. We even get to see Kirk's predecsssor, Christopher Pike, extremely well played by Bruce Greenwood. Some of these characters get more development in this film than in years of television episodes, which is all to the good. I disliked a brief sequence in which the teenage Kirk is a very bad boy, but other than that I believe wholeheartedly in the film's new look at these familiar characters.
As for the plot, it sort of makes sense, much more so than some of the previous Star Trek films. The antagonist is a vengeful Romulan in a horrific, spiky starship, more reminiscent of Babylon 5's Shadows than the old Romulan Bird of Prey design. Although he is defeated at the end of the film, he first accomplishes some terrible things, including the destruction of a planet we care about and the death of a major recurring character. There is no reset button, and the damage stays done at the end of the film, a disturbing turn of events akin to the destruction of Gellifrey in the 2005 revival of Doctor Who.
The result of all this is a clearing away of much of Star Trek's accretion of continuity, and yet most of the basics remain. Kirk is still a bit of a womanizer, with a genius for improvisation and a healthy disrespect for the rules. McCoy is still "a doctor, not a..." and can tell you exactly why did doesn't like transporter beams. There are lots of familiar names of people and places and starships, bits of recycled dialogue to annoy or warm the hearts of longtime fans (perhaps both), space battles, cool effects and soaring, bombastic music.
I can't judge how this film would go over with someone unfamiliar with the old show, but as a fan, I'm hard pressed to see how the film could be much better. Once I accept the cataclysmic events and their effect on the show's continuity (and you know me, I'm a continuity junkie from way back), I can admire how well J J Abrams has refitted my first favorite show for a new round of adventures.