^^
plus one, more or less
I can't speak for others guys, but if I have sex on a first date, its because there's great chemistry, and I'm interested in more than a quick fuck. Moreover, its a great sign that she and I have similar opinions about the place of sex in a relationship, and that we don't have any hang-ups about looking like sluts.
When you give it up on a first date, but don't hear from him again, its not because he thinks you're a slut. Guys LOVE girls who love sex, especially when its sex with them. A more likely reason is that the sex wasn't good (which is usually indicative of incompatibility), or you dated a guy who was really only interested in sleeping with you once, for the experience. If its the latter, consider being a little more choosey with the guys you take home.