Personally I don't use it (not because I have a specific abhorrence of the word, although the act itself is pretty abhorrent), but every once in a while you'll hear things like "boy, our guild raped Hakkar last night," or "stupid elite Son of Arugal just came out of nowhere and raped me." The word for this kind of usage is actually "dysphemism," the opposite of euphemism, in which you specifically use a harsh word in the place of a more polite one.
And that's the problem-- just like "gay," it's not polite to use, not least of all because you may hardly know the person that reads it or their situation. In some cases, the word can be downright offensive. Fortunately, I don't know anyone (that I know of) who's experienced real-life rape or abuse, but especially in an MMO situation, there's no reason to use the harsher word, especially if, as Elizabeth said about "gay," it costs you respect (and possibly your account).
As the WoW Ladies contributor says, "realize there are a lot of women in guild, as well as a lot of married members and members with children. Realize that 1 in 6 women are raped in the US. Realize that each person in the guild is either female themselves, and/or has multiple loved ones and friends that are female. Realize that rape is a deeply traumatic experience, for the victim and their loved ones." Even if you're joking, or even if you didn't mean it that way, it's just not worth saying.