Finally saw this.
It might be my favorite superhero movie. The pacing was great. Pure action movie from start to finish. Clever, funny, witty, with smart use of the Iron Man tech that smoothly escalated through the course of the film.
As for the main criticisms of it, I was fine with the Mandarin reveal. Even going in to the movie knowing the Mandarin was going to be revealed as an actor, Kingsley flat killed it.
And the lack of SHIELD and other superheroes was just right. The heavy-handed crossover of IM2 which dominated the second act really brought down what was otherwise a fine movie. As it stands, the fallout from Avengers was deftly handled without stomping all over the stand-alone integrity of this movie. The world is on the cusp of first contact with gods, aliens, and monsters, and Tony's anxiety regarding that heavily informed his characterization in this movie. He's living in a world that's scared of when the monsters are coming back. He's ruining his personal relationship with Pepper, creating an army of robots in preparation of that unknowable threat. And I at least got the impression that he's got little to no respect for SHIELD. The whole movie was about him coming to terms with the the trauma of Avengers, hiding behind an iron shell, building an army of machines to keep his girlfriend safe while that relationship crumbles around him, and ultimately coming to terms with the fact that he doesn't need to hide behind the armor, because he's not a knight. He's a mechanic. And his super power isn't his suit of armor, it's his brain. Even without his armor, he can face any obstacle in front of him with a credit card and a trip to Home Depot.
It speaks to me of an impressive growth in the cross-universe storytelling at Marvel Studios. Phase one was dominated by a pretty heavy-handed feeling of continuity, from SHIELD's heavy presence in the lead-in movies to those hammy but fan-pleasing post-credit sequences. This is far more elegant. It starts with a man broken by the trauma of being on the frontlines of the world's first battle with the extraterrestrial, caught in a cycle of PTSD, an insomniac hermit too caught up in the comfort of building to even think about what it is he's building. It ends with a brilliant inventor confident in himself rather than hiding behind the identity he's created. It sets up the potential conflict of the next movie with a technology of networked robot-soldier drones ready to be (supposition to follow) hijacked by SHIELD to create a threat they can't control. It sets Tony Stark up as a fully-matured character for Avengers 2, the confident engineer equipped to strategize a solution to the problems looming on the horizon. It honestly may be the strongest example of character development yet seen in the Marvel movies. It just wears that development with subtlety.
I hope Cap and Thor show a similar evolution. I have no clue where they'll go with Thor, but the information out now seems to suggest Winter Soldier is going in the right direction: a movie about a good soldier grappling with a bloated and corrupted military-industrial complex, a well-intentioned institution that suffers from decay within and ill-equipped to actually deal with the problems of the future and how that soldier comes to terms with how to align his values within that complex. I'm looking forward to it. I'm hopeful. IM3 seems to suggest that the films are developing well past the growing pains of the superhero sub-genre.
Finally, with Downey signing a two film contract, and with them preparing a slate of new characters for Phase Three, I wouldn't be surprised if this is the last solo film we see with Downey. They want to insure his involvement in both Avengers movies, which the contract will cover. And artistically, it makes sense. The end of this movie nicely wraps a bow on the idea of Stark as a solo superhero. My guess is we'll see him in the Avengers movies as a financier and strategic advisor who just dons the suit in instances of full-blown global threat. Then, as A3 is rounding the bend and they're looking at the future of their franchises, they'll be gearing up for a replacement actor.