So I just came back from a screening
In my country there's only the 3D version. Almost didn't go because of that. Unnecessary, distracting etc. etc.
Once again, SPOILERS
The twist with the Mandarin. Loved what Kingsley did with it, but I was simultaneously amused and angry. They have gods, aliens and superhumans, but Mandarin has to be a mere puppet?
Pierce as the villain was enjoyable, but I didn't really get why he was so evil. But still, it was Guy Pierce, so I won't complain much.
Pepper's action scenes were awesome! At the end I was a little bummed out that Tony cured her (or did he?) instead of perfecting Extremis and leaving her supercharged.
I enjoyed the narrative. The kid wasn't annoying. More quotable one-liners! Tony kicking ass and taking names without the suit! Post-credits scene!
Overall, I enjoyed it very much and I don't know why some people hate it so much. Sure, it's not perfect (although I'm not exactly objective after just one screening), but it's heaps better than IM2.