Slut carries a very large negative connotation, especially when it's used as you used it. A lot of folks feel that part of letting people feel comfortable about their sexuality is to not make them feel bad about their sexuality by using those kinds of terms in a negative manner or by by the implied judgement those terms carry. Because of that, I and a lot of others who are trying to let people become more sex-positive call ourselves sluts and are trying to make people aware that there is a difference between people who have several sexual partners, including casual ones, and people who don't act honorably towards their sexual partners. -- Anmar Mirza