Psyringe: I firmly believe that no subject should be "banned" from exploring it in art (books, music, games, etc.). Art needs to be free, needs to be able to break taboos, to provide a new perspective, to change our minds.
We may disagree with the way how one specific work depicts a given subject, especially if the subject is a very real issue that often leaves deep wounds, such as rape. But it's also possible to use it in a way that broadens our perspective, that lets us understand things a bit better. And you can't have the latter without also allowing the crap.
Horror movies are certainly a medium where rape is often just used as an embellishment or as a "gore" feature. But there are also works like "Deadgirl" which positively surprised me in the way how they handled the subject.
If you don't like horror movies that include rape scenes, that's absolutely fine. Don't watch them, or - if you do watch them - voice your discontent. But I'd stay away from sweeping statements like "horror shouldn't contain subject X", or calls for censorship (be it authoritative or self-inflicted).
If there's a movie that glorifies rape, or that revels in its depiction, then I will probably condemn this movie with very strong words. What I won't do, though, is calling for it to be banned, or claiming that the subject shouldn't be used at all. We need our minds to be free. Free minds obviously produce a lot of crap, but then we call them out on that.
I never called for censorship. Saying horror shouldn't contain rape is no-more censorship than saying FPS games shouldn't have platforming. That's not calling for governments to ban Mirrors Edge. It's saying, I don't like this and I think we would be better of without it.