I don't think it's ever been ok to call another woman a "slut", custardo. And I've never seen it coming from one of the Mumsnet Feminists.
I'm also struggling to see your points re: the anti-women vernacular. I'm completely lost as to what you mean.
And no. I don't think Rhubarb deserves an apology. She spoke to and about rape victims in a quite shocking manner, assuming that she knew more about our ordeals than we do. She also accused me of verbally abusing her, something which, after re-reading the thread and discussing it with another person, I can't see. For her to accuse anyone of bullying is unacceptable, especially in the vicious manner in which I felt she spoke to several members over the past few days; myself included.