I retweeted this this morning, but reposting here cause its such an awesome blog post.
Basically, this guy (John Willward), registered 10 dummy profiles on dating sites, and monitored them for 4 months.

Nice share! This blog seems to be solid, thank you tijn.
Damn that is a solid post from that guy. Thanks for the info tijn
Pretty Women get more messages, Shocker.
Blog seems interesting though, I might dip my toe into dating offers coming up here soon.
Very nice, going to pass along (will give credit though!!!)
Those experiments were great. I tried to do something along the same lines on POF. Split testing pick up lines, and see how many messages were sent to a profile based on each pick up line. It feel to pieces when POF started deleting inactive profiles
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That was the reason for this initial post: http://www.mrgreen.am/general/wanted...pick-up-lines/
Nice !!! Thank you for this !
Awesome idea Zo. Maybe Ben should help out and allow some of this "research" to take place.
This is why okcupid was so so excellent!
http://blog.okcupid.com/
Unfortunately they were acquired and the posts stopped about a year ago.
no shock, but good info none the less