Carnation brought up a very good point that had completely slipped my mind...
I, being from South Carolina, am also right smack in the middle of the bible belt. The thing is, we have sisters that go out every night, but we also have sisters who have formed chapter bible studies. The problem that you're going to run into, being from the south, is that even in a "party" sorority, you'll find people who's lives revolve around God, and who severely frown upon people who go out (even though their sisters do, they might not like that they do). You're probably better off staying pretty neutral and talking about non-alcohol related interests. Of course, if the girl brings up that she likes to party, you'll have an open invitation to talk about your interest in partying, and that would be just fine!
Good luck!