Sexy, hilarious, and totally amazing. Don't go if you are going to be offended by alternative sexualities. Also, this would probably be a lot more fun if you went with someone you could play with afterward. I went with my mom (who is very cool and loved it), but it just wasn't the same.
EDIT 4/06: I just got back from Vegas where I saw Zumanity for the second time. It was still amazing (can I take the contortionist home?), and several of the acts were different than when I saw it previously. Also, I can now say first hand that it IS more fun if you go with someone you can play with afterward.