What a bunch of morons. Rape jokes don't cause rape, rapists cause rape.
The basic argument is that when people laugh at rape jokes, we're telling potential rapists that it's OK to rape, that this particular form of violent assault is a joke. So they're less likely to restrain themselves when they see an opportunity to rape someone.
That logic can be applied to a lot of things though and ultimately, I wouldn't use that as a basis for a censorship campaign. I find the idea of censoring things to be really abhorrent and have to have a really good reason for it to happen and not be left to one person to decide what's to be censored or not. (And make no mistake, what went on was a censorship campaign and not simple dissuasion, she actively wrote to Hasbro to have that blog taken down.)
If a woman is open about her consensual rape fantasies, is she telling potential rapists that it's ok to rape? Do we then censor women who talk about it?
Or somewhat less related,
If people play violent shooters, are we telling people that it's ok to shoot people in real life? Do we then ban violent video games?