I recently finished reading Battle Royale, by Koushun Takami. A lot of people refer to it as "the book Suzanne Collins ripped off when she wrote The Hunger Games." Both books revolve around the premise a totalitarian government that forces teenagers to fight to the death. However, despite the similar premise, these are entirely different books.
Note: No major spoilers here.
To start off, the characters in Battle Royale are classmates, not strangers, which changes the dynamic a lot. Instead of nameless adversaries, your "opponents" are your friends, love interests, acquaintances, and enemies. Which of them would try to kill you? Would you be able to kill them? Obviously, some turn on others, some form alliances, some go crazy or reveal themselves to be outright sociopaths, and a few of them even refuse to play. A big driving force in Battle Royale is the element of denial. Although the students knew about "the Program," they never expected that their class would be chosen. In The Hunger Games, the members were forced to watch the games year after year, so when it is their turn, they are more or less resigned to their fate, and even when alliances are formed, everyone knows they can't last forever. In Battle Royale, several students are determined to escape. This adds extra tension to the alliances--are your friends really trying to help you, or will they stab you in the back after the numbers dwindle?
A major difference is that while The Hunger Games is Katniss' story, Battle Royale shows the story through the eyes of several different students. This is both a strength and a weakness. I loved that I was able to get to know most of the students, and some of their stories were heartbreaking (and of course, there was one instance where I cheered on a girl as she fought against a particularly heinous opponent.) However, this story is in many ways an allegory, which meant that a lot of the minor characters fell flat (ie, "the gay guy," "the snobby, rich boy," "the weird girl.") One major problem I had was the book's sexism. All but two major characters were male, and of those two females, one was a "villain" (and a considerably weaker one than the primary male antagonist) and the other mainly existed to be the protagonist's sidekick/love interest/damsel-in-distress. (I'm not necessarily asking for a bad-ass fighter, but it would have been nice if she were more developed.) Additionally, I found the portrayal of the gay character offensive. Still, due to the allegorical nature of this book, none of the sexist/stereotypical characterizations of students were a deal-breaker for me.
Thematically, the books are very different. Both deal with totalitarianism and government brutality. However, The Hunger Games deals a lot more with voyeurism and sensationalized violence. The Tributes are dressed up and put on display and their deaths become a public spectacle. The book (well, the first one, at least,) isn't so much a critique against the government as it is a critique of the Capitol citizens, who are shallow, flamboyant, obsessed with celebrities, and perfectly okay with killing innocent teenagers, as long as they aren't star-crossed lovers, of course. The critique in Battle Royale, however, isn't on the society, but on the students. By delving psychologically into the characters, Takami explores brutality, paranoia, selfishness, friendship, devotion, and trust. These elements aren't absent in The Hunger Games, but due to the limited point of view, they aren't explored as broadly as in Battle Royale. (Note: I said "broadly," not "effectively." YMMV on that one.)
Stylistically, The Hunger Games is far superior, although I can't really compare them since I didn't read Battle Royale in its original language.
In terms of violence and gore, there is no competition. Battle Royale makes The Hunger Games look like candy.
So which one was better? I don't know. Instead, let me ask this: Which packed more of an emotional punch? Battle Royale was much more horrific, not just because of the gore, but also because of the sheer level of "wait--this is real" that the students were facing. However, I felt much more connected to the characters in The Hunger Games.
Both books are excellent, and of course, I recommend both.
I'm interested to hear what other people think. Did you read Battle Royale? (There's also a movie and a manga series.)