Michael Bay has nailed the formula for these movies, and he won't let it go, because hey, after all, why break a toy that works perfectly?
This one's a fun ride, with lots and lots of fighting (between robots, non-trained humans, USArmy...), lots of destruction, twists, sacrifice, fun and some classic Michael Bay t&a, which basically just make you laugh.
Though at one point the movie could feel a bit long (when Samy enters a ravaged Chi-Town intent on facing the hordes of Decepticons and save the girl all by himself), the reappereance of a badass Optimus Prime saves it, and it is a merit to director Michael Bay and his Special Effects Studio the slick and smooth way in which both Autobots, Decepticons and US Army synch in a perfectly choreographed battle.
Don't really know about this movie's exact budget, but it must have been a nice effort on Producer's Steven Spielberg part. Every penny spent is worth it (and I watched it in 2-D!).
Some great actors like Frances McDormand (CIA top honcho), John Turturro (a classic in these Transformers movies) and a hysterical John Malkovich help to give the flick a different level than the average popcorn movie.
Shia Leboeuf, Spielberg's prodigal son, nails the classic hero-with-feet-of-clay who even in the third installment of the Transformers saga, gets poorly treated until, after a lot of fighting and shouting, he becomes the not-so-unexpected hero, and the Autobots best ally.
If you like big robots, massive destruction, and a nice dose of fun spread throughout it all, you'll likely enjoy this movie. After all, with the word Transformers on the title, you know what you're going to get...or don't you?
Sam