Iron Man 3 is the what a sequel should be, as good as the original. It's better than Iron Man 2, and equals in many ways the original Iron Man. The only reason one might say it's not as good as the first one, it's because the first one had so many original quirks that are only copied in this sequel.
The good. Incredible action. Seamless astounding special effects. Lots of good jokes. Great immersive photography. Interesting story.
The actors. Robert Downey Jr. and Gwyneth Paltrow were just as good as in the previous episodes, but Ben Kingsley almost steals the shows as The Mandarin. So incredibly surprising.
The bad. The scenario is pretty straight forward and doesn't bring anything new to the table, but who cares? The bad guy is a trifle simple, no depth. No need for 3D, it's just as good in 2D.
The ugly. Nothing.
The result. A must see, unless you can't stand Robert Downey Jr., super heroes, action or bloodless violence. See it on a giant IMAX screen with the best sound even if it means seeing it in 3D, an experience not to be missed.