An average sequel at best. Iron Man 2 is pretty disappointing and nowhere near reaches the height of its predecessor, but it could have been a whole lot worse. The result was a mediocre sequel. Iron Man 2 unfortunately suffers from too much world-building and setting up The Avengers (which it didn't even directly lead up to). The plot is also convoluted, but certainly not convoluted enough for it to be hard to understand the story.

There are also flaws with some of the casting. Don Cheadle was miscast as War Machine/James "Rhodey" Rhodes. Howard was perfect as Rhodey and he would have been a better War Machine.

Sam Rockwell was miscast as Justin Hammer. Marvel should have cast an old man to play Justin Hammer instead of someone much younger. Justin Hammer was an old, white-haired senior citizen with a cane in the comics, that's how he should've been in the movie. Mickey Rourke was miscast as the supervillain, Whiplash. Plus, he wasn't even the same Whiplash from the comics, in this movie, he was a Russian guy named Ivan Vanko who was never ever even from the comics, and Mickey Rourke's Russian accent was bad and unconvincing.

Ivan Vanko was a terrible and forgettable villain and he was underdeveloped. S. H. I. E. L. D. Kept annoyingly popping in and out of the movie.

Robert Downey Jr.'s performance was just okay in this sequel, but disappointing compared to his great performance in the original Iron Man film.

Scarlett Johanssen gives a very good performance as Black Widow and one of the few positives from an average film.