I'm going to start off this review saying that I read Catching Fire in just one day! I'm a fast reader, but not that fast (normally), so it's just a testament as to how much I loved this book.
This book picks up where The Hunger Games leaves off, starting with a background of things that happened immediately upon Katniss' return to District 12. The action really picks up right before Katniss and Peeta tour the districts for their Victory Tour. It was a nice transition between the two books, because as the reader, I didn't feel like I was missing any of the action. Everything that was mentioned as happening to the victors after the end of the Games was actually detailed in Catching Fire. I really liked that the books, together, seamlessly covered all of the time from the beginning of The Hunger Games to the end of Catching Fire without leaving large gaps in time between the two books like some multi-book series do.
Again, Katniss and Peeta are very strong personalities, but you can tell that they have changed since winning the 74th annual Games. They are both more rebellious and more questioning of Panem. This, combined with some other events and new characters (that I'm not going to mention specifically here- too much of a spoiler!), do somewhat prepare the reader for what happens at the end of the book, although not how it actually comes about. While yes, like many other "middle of the trilogy" books, Catching Fire has the role of setting up what needs to be done before Mockingjay, there are enough twists, surprises, and new characters to keep the reader interested from beginning to end. Even changes in characters that we met in The Hunger Games feed into the unrest throughout Panem. Effie, Cinna, and the rest of Katniss and Peeta's entourage become deeper characters in Catching Fire, again to the effect of expressing the state of the Capitol after Katniss' defiance at the end of The Hunger Games.
I especially like that Collins is able to plant doubts into the characters' heads (especially Katniss') at the same time that she puzzles the reader. Again, the first person narration helps a lot. The plot moves quickly, and the reader really experiences what Katniss does throughout the entire book.
While I can't deny that I did like The Hunger Games more than Catching Fire, I think that was mainly because everything was so new in The Hunger Games while a lot of things were more expected come Catching Fire. That's not to say that I didn't still love Catching Fire- because I did- and there is absolutely enough in there to keep the reader pulled forward. It's just that The Hunger Games had more straight-up action because it primarily dealt with the Games themselves, while Catching Fire covered more of the political unrest and character relationships.
Wow~ I can't wait to read Mockingjay next! Just seeing reviews of Mockingjay are what got me started with this series in the first place. But, more of that in the appropriate review!