Just in case <<<BIG SPOILER ALERT>>>.
I'll say that overall, the film was good but it wasn't great. They wanted this story to be a bookend to an Iron Man Trilogy, a way way for Tony Stark to go to the next level, for him to get a little more serious, and I think they accomplished that much. But they broke the CARDINAL rule of any sci-fi/fantasy story - you have to set up the rules of the magic/technology and NOT BREAK THEM. I might need to rewatch the show but I didn't feel like they ever properly set up the rules for what the limits of the Extremis augmentation were. At first I thought that it just allowed them to regenerate and have a healing factor, but it created a lot of heat as a by-product/side effect and it was dangerous and unstable so you have guys sometimes exploding at 3000 degrees. So when they show the bad guys trying to cut their way into Rhodey's armor, then Guy Pearce slowly heating up Rhodey's armor, and then later Guy Pearce is literally slicing Tony's armors in half with his bare hands with pure heat, but NOT dying or exploding, I was like "Give me a break." Instead of loving to watch augmented humans go toe-to-toe with suits of high-tech armor (which sounds awesome), I was calling BS. They had set up how awesome and powerful these suits are, and how the Extremis augments were powerful but unstable, but then the Extremis augments are kicking all this ass and I just couldn't buy it.
I did like how central Pepper was to the plot, and I liked Happy's role - that he was doing some things that mattered to the story, that he uncovered the first clue that leads Tony on his detective hunt, I liked seeing all the suits in action (but yes, it would have been nice to see more about their specific uses...), and I LOVED the Mandarin twist, but I was waiting to see him get tied into the Ten Rings that was set up in the first film! Even if it turned into a false trail and they were like "Oh we just used the logo, the real Ten Rings had nothing to do with this." You were good, Shane Black, but... lacking. Hoping that the DVD has a lot of goodies or I won't be adding this to my collection.