I think I'll say right up front I thought the movie was alright, not great but alright. Not sure if it was worth the money to see it at the theater though. Now on to my other opinions.
Michael Bay should move on from movies and do what he seems to really love, and that is commercials. Outside of this movie being made from a Toy Line, he can't seem to stop the salesman ship there. Sideswipe, or was is Sunstreaker? Can't remember since he was barely in the movie. He was supposed to be a Lamborghini, like he was in the cartoon. Cool. Instead Bay changes him to the Corvette concept because GM wants him to. Then because GM wants to create interest in a new car Bay creates a new transformer called Volt. It didn't exist before the movie started so he writes the new transformer into the movie while shooting. It's the new Chevy Volt, GM's electric cart. Not cool. Of course after that there is a ton of loving shots of products, like Cysco, through out the movie.
When you hear a environmentalist talking about recycling, I don't think they means what Michael Bay thinks they do. Recycled locations, check! Recycled Transformers models, check! I am also pretty sure he recycled the shots of the carrier from Perl Harbor, I know he reused it in the first movie.
This movie centers on Sam Witwicky (thumbs WAY down), Optimus Prime (thumbs up, though he does disappear for a time) and Bumble Bee (never was one of my favorites but still a thumbs up). The movie has a very chaotic story, it really feels as if it was written by a 5 year old on acid. That is if you can even notice one. The new Transformers added to the movie they were hyping play no real role in the story at all. The only new transformers to play a role are The Twins, and they are annoying. Personally I would call racially insensitive instead of racist, but I have no doubt the idiocy on display with a caricature of inner city black men as it's basis and I think more then a few people were offended. Most of the new Transformers just show up at the beginning of the movie to chaise down a couple of nameless Decepticons and then they play small role at the end. On the Decepticons side outside of Megatron or maybe even less so Starscream and Soundwave play a little role in the movie. Even the big new bad guy doesn't even merit much of a role. He just shows up once before the end, and then appears so Optimus Prime can kick his ass.
If you were a big fan of Devastator or Jetfire, let's just say you're not going to be happy.
On the up side, Optimus Prime kicks way more ass in this movie.