I saw a preview screening last Friday night and I enjoyed it, though I did have some problems with it.
The computer hackers thing was totally pointless and unecessary, though; they took up valuable screentime which could have been given to Jazz, Starscream, Barricade, and Ratchet. And I did not like the GM product placement, but a necessary evil I suppose, to get the film made.
Peter Cullen as Prime is magnificent. Even when he has to work with cheesy dialogue, he gives it dignity and gravitas. Hugo Weaving's Megatron sounded so similar to Welker's that I could not understand why Welker was turned down.
By bigging up the US Army (you can tell Bay added that), Bay undermined the Autobots role totally. When Prime confronts Megatron, it should be the case that Prime is the ONLY thing standing in Megatron's way.
I do wonder if Bay grasps the concept that the Transformers are pretty much the same as humans.
Jazz deserved much more screentime, as did Ratchet (there was plenty of opportunity to show him, trying to save Jazz and fixing Bumblebee etc, or even saving a wounded human). Jazz, Starscream (he only got 2 lines I think, thats crazy for a big character like him), and Ratchet were underused.
Alot of film critics talk bilge about Transformers, moaning about it being based on a toy line. Pirates of the Carribean is based on a theme park ride, Harry Potter has merchandise all over the place, as does The Simpsons, and I don't see critics taking the moral high ground on those.
I am definitely looking forward to a sequel (Shockwave/Starscream, Optimus Prime/Grimlock rivlaries perhaps?).