^^I'd offer it more than once. That's a very dangerous thing to do, if she's advertising that she's ready to lose her virginity. A lot of internet predators thrive on things like that, on CL and Myspace. She could get herself into a lot of trouble. Someone might seem nice, but just a few ways down the road, dark clouds may start to form and she could find herself the victim of a sexual or physical assault. And people carry diseases, and I hope your friend realizes the danger she could put herself in by advertising herself that way.
I've met people off of CL before. In a public place, always at daytime, and I never let them pick me up, drop me off, or walk me to my car afterwards. Until you have several PUBLIC meetings with someone you meet online or through a friend or dating service, you really shouldn't be taking to to an intimate level, because you aren't able to establish trust with someone after just one or two meetings.