I liked and enjoyed a great deal about this book - that Katniss and Peeta's victory had consequences, that the rebellion storyline smoldered before bursting into a wildfire (yeah yeah, I know what I did there) at the end, and that Katniss was faced with difficult decisions that she weighed, and had to consider, rather than all the pieces just falling into place.
What I didn't like was the Gale/Katniss/Peeta storyline. That's not to say that I don't like the idea of Gale/Katniss. And I am whole-heartedly smitten with the idea of Katniss/Peeta. What I liked so much in The Hunger Games was that we saw Peeta's love emerge as real, and not just a smoke screen or a ploy for the Games, and that Katniss didn't know how to feel about that. I didn't feel like the love triangle arc needed to be fleshed out. I would much rather Katniss have simply remained conflicted over Peeta, and consider Gale her best friend. In this story, I wasn't a fan of the "seeing my best friend nearly beaten to death (or insert tragedy/epiphany here) led me to realize I was in love with him" device. I think that's something that only rarely works and here, it felt very sad, and immediately took on a "doomed love" type feel for me, and I didn't feel like that worked, here.
I also wish the book had been a little bit longer. Collins covered ground fairly well, but by the time we saw the characters get to the Games, it felt like the book flew by. I would have loved to have seen that part of the novel fleshed out a little more.
But overall I really enjoyed the book. I cried more than once, and what I love so much about the books are that they make you think. They are a "what-if" that trembled and topped off the edge into a cold reality. And Katniss truly lives up to the definition of a heroine, with some admittedly human moments. I look forward to "Mockingjay."