Reposting from last thread.
List of spoilers from that /co/ thread.
Less spoiler-y stuff:
-SHIELD has a minimal presence in the film
-The Mandarin is pretty humorous and his rings really do cool things, not magic like in the comics though
-The movie is funnier than the trailers let on. About 70% serious 30% funny
-Most of the major plot points have been revealed by Marvel already, we just didn't realize it
He also says that the film has more of a sense of urgency than Iron Man 2.