My two cents worth:
Downey Jr. was brilliant as Stark. Bridges was brilliant as Stane. Although I was disappointed that Rhodes didn't go to Gary Dourdain (of CSI fame) I thought that Terrence Howard (sp?) was perfect. Gwyneth Paltrow didn't bother me as much as she usually does. Even
Spoiler:was good casting...he was, after all, the model for the Ultimate version of that particular character, and I've noticed that recent Marvel movies seem to be drawing partial inspiration from the Ultimate universe.
Samuel L. Jackson as Nick Fury
The CGI was slick, the designs were perfect, and if the action moved rather slowly, it is because Favreau fully intends this to be a trilogy, and the first installment in any trilogy has to bear the burden of exposition.
I like the way everything was handled, including the updating of Stark's accident and captivity from Vietnam to Afghanistan.
Having said that, my only concern was this: Stark is supposed to be a brilliant engineer, and good engineers design redundancy into EVERY system. Thus,
Spoiler:
why did Tony not have a spare of his most recent arc reactor? Having to use the old one to power the suit for the final fight seemed contrived.
Other than that, I thought the movie was spot-on. Granted, Iron Man has always been one of my favorite Marvel heroes (I like the idea of the smart guy with no superhuman powers who uses his brains and technology to do what he does), so I might be biased. But there you have it. I plan on seeing this again.