Great acting by just about everybody - Downey especially. I'm mixed on Gywneth Paltrow, but she plays the role she's given well enough. It does everything it should, makes few (if any) mistakes, and tells the superhero origin story nicely. It's a ridiculously fun popcorn movie that isn't empty (transformers, x3, etc), and the story makes a reasonable amount of sense (also transformers, x3, etc). Well worth your $10!