I know a couple of OKC founders. They are hardcore math/statistics geeks. I'm sure they realize the quality of their service matters more than making a bit of money quickly.
They are doing pretty well, considering their competitors have ads on TV.
They have produced some really cool blog posts, which I enjoyed reading. The site itself is fun, I've had 2 accounts on there - 1 I used in London, 1 in Shanghai.
I got some profile views and a couple of conversations, but never met anyone through it; with the exception of seeing my co-workers on it, in Shanghai.
In each city, within a few weeks of creating a profile, I've been in a relationship, but not through the site.
They are doing pretty well, considering their competitors have ads on TV.