Transformers 3: Dark of the Moon was a good movie.
OK, now that I have your attention, let me explain. I've seen better movies, but I haven't seen a better Transformers movie, and even when compared to blow-em-up summer tentpole movies, this one is pretty excellent. First, let me cover its flaws, and then I'll get into a spoiler-free list of what I liked.
The biggest problem with this film is its running time. At 157 minutes, it's about 45 minutes too long, at least. The plot isn't that complicated, but there are a lot of moving parts, and every character has their establishing scene, some cute jokes and a later thread in the climax. There's some weak scripting work here, where a good and disciplined screenwriter could have combined some of those threads and still done justice to all of the characters.
That said, there are some characters that need to go, though. The parents just aren't funny, and I know everyone loves the goofy spy, but I'd forgive Bay if he flushed this character down the drain. Ditto the cutesy tiny Autobots.
The replacement hot babe is forgettable. She seems capable of saying her lines, posing and screaming on command, but she's never given anything else to do, which is a shame. Perhaps less time spent on her underwear and more time spent using her like a Doctor Who companion would have helped negate the need for a good deal of Sam's parents and his own whining. Speaking of Sam's whining, the alternating whining/bravado thing gets old around minute 7 and stays that way until about minute 155.
So, why did I like such a flawed movie? Where to start? It's a 3D movie that's enriched by 3D, but absolutely doesn't need to be seen that way. It's funny. The sheer volume of self-aware, self-referential, and genre in-joke one-liners in this movie is shocking. The CG is art. Flat out, art. If you come away from this movie saying, "great CG, but there's no art to it," then you're just stuck in the mid-20th century. I'll grant that, like the great album covers of the 80s, Transformers's art is communicating in the language of male teen heroic fantasy, but it's still art.
I'm also stunned by the cameos, great supporting characters and some of the nods that are made to previous appearances. Just reviewing IMDB (no spoilers) you have Leodard Nimoy whose last Transformers appearance was in the 80s animated movie as Galvatron. There's also John Malkovich and Alan Tudyk, both of whom could probably get me to go see a movie I would otherwise avoid, and they don't disappoint, here.
The action scenes are truly impressive. There's one slow-motion sequence that's pure genius, and must be seen to be believed. You'll know it when you see it, but just in case you were not sure, it involves a tire being batted aside.
My only real complaint that I voiced coming out of the movie, besides the running time, was the physics. Yes, I know that it's a fantasy, and we're not supposed to be questioning the physics, but it's pretty glaring. There are times when Sam should be turned to paste because he's experiencing G-forces far beyond what a human can tolerate. There are the usual stupid "run through window and live" scenes, but it's even worse, here. Still, you didn't go in expecting accurate physics, right?
Overall, I'd give it about 4 out of 5 stars. Much as I enjoyed it, I can't reasonably give a full 5 stars to a movie that drags on as much as this one does.
PS: Bonus points to anyone who points out at least 2 Star Trek references from this film in the comments.