A pretty good follow up to The Hunger Games. Like The Hunger Games it has nothing original about it, and what makes the book good is the strength of the writing and the characters.
Katniss is a good character. She is sort of a dope about certain things and does not understand people all that well. That means that the end twist, which I saw coming a mile away is not quite so offensive because she is meant to be slow on the uptake. She is a good character. The dystopian world remains unoriginal and well executed. Katniss becomes a figure head of revolt. That could be poorly executed, but is done well.
The writing style is well done. The violence is real but tasteful and it is well paced although the plotting is conventional. These are hardly revolutionary books. They cover ground that has been covered a million times before, but they cover it well. Collins is a good writer, albeit a derivative one.