I saw it this morning. I wasn't going in expecting an epic story the questions the very essence of our being. Really I wanted to see more robots and less people with fight scenes that actually occurred on screen. It didn't disappoint in that area.
The biggest detractors were the "Twins" which were annoying little redneck robots, making more of the characters memorable, and sometimes it was hard to tell what was going on.
Some of the characters were great. Jetfire was a class act grumpy old man. However I think they only said the name of Megatron's superior once, and I missed it. I also don't remember the names of the Autobot disguised as the Corvette concept, the Twins, or the little robot the turns into an rc truck.
As far as plot goes. It's all there, but not told as clearly as it should have been. They didn't explain what Energon was until well after the name first came up. Ratch has no lines in the whole movie. Barricade wasn't there, and a few other continuity errors.
Still, the fights were a lot better this time, and there was a lot more of them, there's plenty of dialogue between the Transformers that pay homage to Gen 1, as well as plenty of symbolic stuff. Which is what I went there to see.