I think there is a flaw in using Facebook friend connections for a dating site. Facebook friends are not the same as real friends, since the barrier to entry usually is just recognizing the requester and clicking accept. Of the 100+ "friends" I have on Facebook, maybe 10 are real friends (defined as people I regularly talk to or hang out with in person). I wouldn't feel comfortable introducing someone to "that girl who lived down the hall from me freshman year who friended me on Facebook"