Is any serious scammer going to be deterred by needing to obtain a facebook account with 50 friends?
I use AdultFriendFinder myself, and if I only go by profiles and messages and MSN/Yahoo/etc. chat, then it's easy to get 50 out of 50 girls in a week not actually be willing to meet and only be after getting me to register on a site for their kickback.
I've never been asked to do that on AFF's internal chat/webcam option, however. So even though profiles and messages and mainstream chat are a heck of a lot easier, I never do them any more. If a site can cut out the spam accounts, they could have that easier service in a workable form.