Oh gosh, I'm happy I read this knowing full well my library copy of Mockingjay had just come in. The cliffhanger would have killed me.
Seems like the second book in a trilogy is usually the weakest. I can't judge until I've read the third, but Catching Fire holds up pretty well. It doesn't match the frantic, deadly tone of The Hunger Games, but it's good. It continues the story in a believable way, keeping the action going. I was a bit disappointed by the pace of some events. It seemed as though the author would describe one day in detail and then skip over weeks in a few sentences. It kept the book going, but it constantly felt as though I was missing something.
My other complaint is about the details given about the setting of this series. This book goes into more detail about each district, but I never felt "anchored" by any of the locations Katniss found herself in. How far apart are the districts? What's the climate like? How far is the Capitol from everything? It seemed as though Katniss should be taking everything in, as an isolated resident of one of the districts.
Besides those two qualms, I think this is an excellent bridge between the first and third books. Now I have to devour the next.