Our research team at UC Berkeley wrote a paper this year about stated preferences for a mate and actual communication behavior in an online dating system. It’s called “Who’s right and who writes: People, profiles, contacts, and replies in online dating,” and I’ll be presenting it HICSS 43 in January. Here’s the abstract:
In this analysis of profiles and messaging behavior on a major online dating service, we find that, consistent with predictions of evolutionary psychology, women as compared to men state more restrictive preferences for their ideal date. Furthermore, women contact and reply to others more selectively than men. Additionally, we identify connections among messaging behavior, textual self-descriptions in dating profiles, and relationship-relevant traits such as neuroticism.
And here’s a figure from the paper showing what ages people say they’re seeking as well as the ages of the people they actually contact and reply to:

I love this! I’ve read more than enough dating profiles to notice patterns and wonder what an analysis would find. I’ve studied enough psychology to know that people don’t know what they want even when they think they do.
What’s interesting here is that they actually DO know what they want when it comes to age. Ethnicity is another story — although it’s hard to say whether the mismatch between stated preferences and actual behavior with respect to ethnicity has more to do with not anticipating whom one will like, or with not wanting to appear prejudiced.