Iron Man 3
I saw Iron Man 3 on the Swedish premier this Wednesday, in short, as much as I love the first Iron Man movie and how it executed the origin story I think Iron Man 3 is probably the best of the three movies. If you liked the prior ones you'll probably like this one.
Some more detailed thoughts below, I'll avoid spoilers.
The story borrows a lot from the Extremis story line, Iron Man Vol 4 #1-6, 2005-2006. I say borrow as it uses a lot of it but is not a complete recreation. For the parts that doesn't stick to the comics there was really only one part I kind of disliked and that is exactly what extremis is, in the comics it's based on nanites while in the movie it has been changed to bioengineering, rewriting DNA. While you'll have to suspend your disbelief in both cases I for one find it a lot easier with nanites than with rewritten DNA for instant effects, specially with the effects it has...
An addition to the story is of course the Mandarin. I won't say much on that to avoid spoilers but I'll say this. Based on what I know of the Mandarin, which admittedly is limited since I haven't yet read any of the comics with him in them, I can imagine that a hardcore fan of the comics might be disappointed with how they handle it but I liked it and felt it worked well for the movie.