The OkCupid blog from before 2011, when Match bought them, was great:
https://web.archive.org/web/20110113034228/http://blog.okcup...
The original nerds who started the site did a bunch of data analysis. Summary: men wildly outnumber women, women feel overwhelmed, men inevitably become desperate, and stated preferences don't reflect actual evidence at all. For example, I recall them saying that women would say they would never date a guy who posted a shirtless photo, but every shirtless-photo-posting guy who looked even slightly decent got way more matches. Also, the data on racial preference was pretty sad.