Saw the film. All I can say, sans spoilers, is that the film was stupid fun. If you try to think too hard about it, like if you ask yourself whether you buy any of the coincidences or if you try to do the slightest amount of analysis of military strategy/tactics... just forget about it. Instead, Star Trek is all about going back to the original characters and romping around with them for a while. They gratuitously have the Star Trek characters saying things that we all know are catchphrases from the TV show (e.g., Bones to Spock: "Are you out of your Vulcan mind?" or "I'm a doctor, not a XXX.") Kirk is precisely the womanizer you'd expect him to be.

Pretty much my only complaint is that they followed the shaky-cam style of film-making, which made the fight scenes very difficult to watch, particularly as I was in the third-row of an IMAX theater. When the action got moving, it was all just a complete blur.

As to Terminator 4, I dunno. I'm following the Sarah Connor Chronicles, and they're certainly worth watching (hey, anything involving Summer Glau kicking ass is worth watching), but I'm not sure about the film. The previews make it seem like they're borrowing a lot of footage from the Transformers.