For anyone who has seen the first Iron Man you can expect much of the same in this movie. Robert Downey Jr. plays Tony Stark like he is meant for the part. He has the same sarcastic wit and self-confidence that is evident in his other movie roles. Gwyeneth Paltrow, as Pepper Potts, has a comes more to the forefront in the sequel. I also personally love that Jon Favreau is the driver for Stark/Potts, and that he gets into the action a little bit. You have to respect the director for that, even though Jon has done plenty of acting himself.
Normally in when they replace someone in a sequel with a different actor/actress I am very upset. However, Don Cheadle replacing Terrence Howard in Iron Man 2 as War Machine/Lt. Rhodes made me happy. This is similar to what happened with Maggie Gylenhal in the Dark Night.
Samuel L. Jackson playing Nick Fury has a bigger role, and it leads all the viewers into wanting The Avengers movie to come out immediately. Scarlett Johansson also showed up with some impressive stunt work, along with her always gorgeous looks.
All in all it was a well done sequel. The plot is not too convoluted to follow. The new villain, played by Mickey Rourke, is very impressive and fun to watch. The action scenes are all entertaining but they do not completely drive the movie. The only thing that I wished for leaving the theater was a longer final fight scene.
Also, make sure to watch after the credits!! It is short, but worth it.