Saw it last night. Bay's action can be tough to follow on its own but try it with crappy seats like I had.

It was entertaining but ultimately I walked out of the theater feeling very empty. Once again CoGro sums up the film's issues perfectly. I feel TF1 is the stronger film.
Rants forthcoming:
The biggest thing I was disappointed with going in and now having seen it is the complete lack of characterization or development. New characters get no introductions, little screen time and next to no lines. Pretty much defeats the purpose of new characters. This was really Optimus' movie but even he didn't evolve much at all other than becoming more of an ass kicker compared to TF1. Ironhide and Ratchet who had a lot of potential to be great characters from TF1 are reduced to the background. The Decepticons are still are treated as monstrous cannon fodder rather than attempting to give any of them other than Megs & Screamer any personality.
The Fallen, for being the title character turned out to be a pointless and unnecessary new villain. He really didn't get much revenge did he? Tony Todd was excellent as the voice though.
I didn't care for Megatron being reduced to a lackey. That's just not his character. I would have preferred that he was only following the Fallen to further his own agenda and was maybe plotting to overthrow him at some point. Didn't like all the "Master/Apprentice" jargon either, save that shit for Star Wars.
The Megatron/Starscream relationship was great but still felt Starscream was lacking some of his other traditional character traits. We saw the suck up, lackey side of him but not his treacherous backstabbing conniving side. At least he survived like the coward he is though. I love the part where Megatron slaps him with his own arm.
I liked Soundwave's role in this film and I really didn't mind that we didn't see him come to Earth or transform. It would have been nice if they could have added just a little bit of the vocoder effect to his voice but it still worked well with the Dr. Claw voice. Very sinister. (According to Robert Orci, Bay would not go for the vocoder effect at all) I also wish he had said his classic line "Ravage eject. Operation: ---" when he dispatched Ravage. And Ravage was very cool too.
Pacing is a huge issue in this film overall and in individual scenes. One such scene is the resurrection of Megatron. Should have been a slow paced and very creepy scene but it's over in a blink. The Doctor asks for parts, they kill a Decepticon and next shot Megs already has his new body and he's blasting for the surface.
They seem to also have a problem keeping track of characters. Wheelie disappears shortly after they get to Egypt. The Twins are MIA after they take on Devs. Not sure what happened to the Arcee triplets. Did they die? One of them did get shot. Barricade was MIA (again). Then there was the CG model reuse. Bonecrusher is clearly seen in both truck mode and robot mode in the final battle. Then there's Grindor/Blackout.
On to Devastator and the Constructicon conundrum. Devs was spectacular from a FX standpoint but was disappointing overall. No real buildup to him, his combination sequence is awesome but then they cut away from it killing the suspense. It's a shame he wasn't used in the final battle more but considering how incredibly complex and difficult his model was for ILM (it melted a workstation!) I'm not too surprised of his screen-time.
Jetfire (aka Mr. Exposition) was awesome. Loved his character. Only problem was he talked way too fast and his voice seemed to change between sounding british or sounding like an angry pirate.
Wheelie I also loved (except for the leg humping scene).
I didn't have a problem with the Twins. I don't think they were really spotlighted as much as some people say. I think it might have been more fitting for their characters to have kept the Ice-Cream truck forms. There was really no explanation as to why they took on the Chevy modes.
I really enjoyed the opening and Shanghai sequence. I thought those were well done. Too bad Sideways was killed so quickly albeit in a very cool manner.
Optimus vs. Megs/Screamer/Grindor was awesome. Probably the best set piece of the film.
I think that's enough from me for now. So overall, entertaining but hollow. Lacking much of the soul from the first one. Despite my long list of sheep complaints I still can't say I
hated it. I will be going to see it again in IMAX and certainly look forward to the Blu-Ray.