I saw the film last night at midnight. I thought it was pretty good. I have never seen Battle Royale or read the book series.
What was irritating about the movie was the shaky cam in the second half of the film. It also felt like the ending was rushed, which is a really bad feeling to have in a movie that lasts two and a half hours.
Woody Harrelson as the drunk mentor was awesome. Jennifer Lawrence was hot and acted fucking circles around Kristen Stewart.
All Twilight comparisons are fucking distinguished mentally-challenged. There's a love story, but it's not the focus like it was in Twilight.
Also, I just picked up a copy of the novel. It's definitely a "tween" book and is not going to be at an adult level, although the book is even more violent than the film.
SERIOUSLY FOLKS, PULL THE CAMERA BACK AND FILM THE VIOLENCE AT A DISTANCE. The shaky cam only nauseates me. Other than that, the film was enjoyable.