As a male, I refrain from using the word "slut" in forums just because it may be offensive to some. I applaud those women who are trying to reclaim the word as their own though, for example in books like "The Ethical Slut" by Dossie Easton and Janet Hardy. Personally, I love women who are positive about sex and willing to get what they want in defiance of stuffy conventions.
If I ever used the word it would be as a term of loving endearment, but until most people see it that way, I will continue to avoid it.