I have already seen this movie twice, and I have to say that the writers and director of Iron Man 2 did a pretty good job with it. I'm not sure if I like it as much as the first one, but it still embodies what the first movie did. It still has the good acting, cheesy one liners, and comedy sprinkled throughout. Robert Downey Jr., as always, did an amazing job as the genius playboy, Tony Stark. Gwyneth Paltrow is back as Pepper Potts, and Don Cheadle steps into the role of Tony's best friend, Rhodey. There are also some new characters introduced in this film that we will see in the next Iron Man movies, and The Avengers movie. One of those characters is Natalie Rushman/Black Widow played by Scarlett Johannson. I'm not going to lie I absolutely love Scarlett, so that was one of the main reasons I went to see this movie. I felt like her character sort of lacked personality until she became Black Widow and had her "fight scene." I hope this is what the writers were going for. If not I hope they bring her back to give her another shot. ;)
Anyway, this movie is about revenge against Tony Stark and Stark Industries of course. Just like in the first movie. A character called Ivan Vanko, played by Mickey Rourke, is after Tony Stark because he wants revenge for his fathers death. He blames the Starks for this because Tony's father fired Ivan's father for stealing Stark Industries secrets. Of course Ivan is a mad scientist and steals the idea of the Iron Man suit and puts a little twist on it to try and bring Tony/Iron Man down.
Overall I would say if you liked the first movie then you are sure to like the second one. ;)