It's bad in the same way that Grand Theft Auto is bad. It isn't child friendly at all, but it's up to the parent to gauge whether their kid will take it to heart or not. To me, it depends on the kid. I know several barely age nine who play Halo and the like. Yeah, I wouldn't want them to do so, but they're well adjusted enough not to do anything stupid. Same goes for ones who listen to rap/hip hop. The real stuff, not the pop shit that's out now.
In short, I believe that parents should be use their best judgment when it comes to their kids. Be wary, but not overprotective.
In short, I believe that parents should be use their best judgment when it comes to their kids. Be wary, but not overprotective.