Jumping in here to say that I agree, and not just in fandom--I've seen its rampant abuse on feminist blogs of late. People feel entitled to say whatever they want to those who disagree, provided that they can identify their opponents as being more privileged along some axis. This in turn leads to some amusing Oppression Olympics (e.g., "I'm entitled to call you names because, while you are a woman, I am a transgendered woman of color with a child." Response: "Oh yeah? I'm a working-class woman with clinic depression, so screw you, and here are some names for you too!").

None of this really helps either discussion or social justice, though it may give some a temporary glow of self-righteousness.