Sure, if they're jerks. I've generally found that guys who label girls sluts tend to grant themselves such charming labels as "virgin surgeons" and freak out if a girl they're dated has so much as kissed another guy.
In the end, it plays out like this: any guy who insists a woman who has more than a few partners is automatically a slut isn't just a jerk, he's probably bad in the sack. A lot of the guys calling a woman a slut want a woman who hasn't had a lot of partners because they're insecure about how they'll measure up, so obviously it's her fault he can't be bothered to, say, ask her a question or listen to her. A sexually experienced woman is a threat to their carefully constructed self-image of not being a total douchebag.
I've had partners that are virgins and who are far more experienced, and what I've found is the best sex comes from people who know what they want in bed. You only learn that from, you know, actually having sex. Any guy worth doing it with, let alone worth being in a relationship with, will respect that. So don't worry about being labeled a slut; just be safe, be healthy, and enjoy yourself.
RF you pretty much just made my day by answering my question--I've been reading you guys for a while now and really appreciate what you all do; seeing mine posted on the home page was extra special.
Thanks for the thoughts! Now I'm going to get off the comp on a friday night, there's sex waiting to be had!
(Just kidding. Sort of.)
RP: I think you avoided answering the question as it was directly asked. Being labeled / considered a slut is all about perception. In my own experiences (and in talking with many other guys), the perception is that if you are female and you sleep with multiple people in a short(er) time span, then you are a slut.
Elizabeth: The long and the short is no matter how many guys you have sex with, in whatever time span, some guys will label you a slut. Whether you let that bother you, or it affects a potential relationship is up to you and your potential suitor respectively.
Which is why they go for married and taken women instead because they're not sluts. If a woman doesn't want to commit, she's also a slut.