I think you might be suffering from a bit of fan boy puppy love this time around Bob. I found Iron Man 2 a significantly less interesting and fun movie than the first. And tying this into the current thread regarding the avengers, I think the primary issue with the movie was including shield at all!
Now before you all get your panties in a bunch, I'll state on the record that Iron man 2 wasn't a BAD movie. It just wasn't good, and the worst thing is that it had the potential to be SO much better. Just by tightening the story and removing some of the truly unnecessery elements, change the pacing a little, and give the bad guys more character development time, and you got a good film. Lets break down exactly what did go wrong.
First off, there's the entire protagonist deliemma we're presented with. Stark spends the ENTIRE movie trying to deal with his daddy issues and his mortality, only at the 11th hour to look at a model of a city, que the flashbulb light on how to solve the paladium degredation issue, and hes fixed! The entire plot of the story essentially boils down to this
Tony Stark: "Oh noes, imma die! Better go out with a bang!"
1.5 hours of going out with a fizzle. Time to wrap things up.
Nick Fury: "I am sick of the motherfucking sickness in this motherfucking hero! Fix yourself!"
Tony Stark: "Why didn't my daddy love me. Oh look, old behind the scenes footage! Daddy DID love me!"
Robot AI butler: "It is impossible to create a new power source master."
Tony Stark: "I'll show YOU robo butler! Get me some duct tape, captain America's shield and a large hadron collider!"
Robot AI butler: "You have created a new element in 5 minutes. MACGRUBER!"
Tony Stark: "I win!"
Make out with Pepper Pots.
Fin.
Now it's easy to poke fun at this plot, because the simple premise of it is redicilous. WHY spend an entire superhero movie watching a rich kid chuck a tantrum only to resolve all his issues in a 5 minute building montage scene with ACDC playing in the background? And even THEN it was a relucatant return to stark's history. The writers seemed adamant on including as much S.H.I.E.L.D action as possible, all to no avail. the bad guys got NO airtime, there was no character development, the love interest plot with Peper was back to square 1, nothing really HAPPENED! I can't fault the acting, nor the cast, nor the action. Just the plot and the pacing.
See, this is why writing is so important. The cast was excellent, every actor put their A game, but they just had nothing to work with. Even the fight scenes played second fiddle to Stark's shannegans, which with the proper script would have been great, but simply fell flat due to uneven pacing. There was just such a high level of inconsistency and lack of overall direction. If anything, Iron Man tried to do TOO much, then realized it only had a set amount of time to play with and tried to wrap everything neatly in a bow.
Take ScarJo's character. Sure it was great to see such a high class hottie in some tight leather, but exactly how would Iron man have suffered had she not been included? Seriously, her ONLY relevant addition to the entire movie was stopping the hack on War Machine, which could have been achieved by that negative nancy robo butler ("I cannot hack the suit remotley, we need a babe in leather to fix this situation). This same concept applies to the entire shield involvement in the movie. Save it for the avengers imo, let Iron man be Iron man and keep the universes and movies separate.
Now I am excited for the Avengers as well, but if Iron Man 2 has shown us anything it's that you should keep comic book movie adaptations in their own micro bubble - Tie it together like with the bonus scene at the end of the first Iron Man, and the End of Iron Man 2. Thats fine! But don't think for a second that explaining how stark got to be part of SHIELD in Iron Man 3 Means you don't have to explain it in the Avengers Movie.