They've been advertising this on Howard Stern for a while. Even he was reading the ad one day and just stopped and was like, "What the fuck? Is this for real?"
Anyway, I assume it's a horny guy/escort hookup service - maybe closeted gay men, too. I just don't see married or single women really wanting or needing this.
They also bought advertising during Larry King on CNN! Saw the ad last night, my jaw dropped open, then I went to my computer to look up the addy... couldn't believe it.