Yeah dating is interesting -- if you can solve two problems and get people to know you've solved it (or at least made the situation better) -- you probably have

Yeah dating is interesting -- if you can solve two problems and get people to know you've solved it (or at least made the situation better) -- you probably have something viable. First is supply -- just having lots of available people on there. It's a classic network that derives its value from the connections. So you could break down barriers like cost (plenty of fish) or complexity in getting a profile up. Second is quality. This is where barriers are important -- Christian dating becomes a prefilter that reduces the population but increases quality. eharmony.com actually actively tries to increase quality by returning NO matches for people who 'fail' their personality tests. As controversial as that is (e.g. if a user is a depressed Atheist, then they probably will get 0 matches) -- it serves the community by making the dating pool better for their targeted audience. The two existing ways in which sites attack these problems is that they specialize for a specific niche and make it awesome for a particular type of person, or just go for pure quantity (which makes sense for an adwords play). Are there others?