Listpic is a really neat site - it allows you to browse through craigslis by viewing all of the pictures posted in the given category. So, I decided to look through the personals section, viewing all categories to get a cross section of how people across the spectrum choose to represent themselves to others. That link is by no means work safe, and if you are fragile of mind it will leave you twisted.
It is definitely a data point, and there are clear patterns that jump off the screen. Mostly in the form of cocks. Lots and lots of cocks. Second to pictures of guys showing off their schlongs for the world to see, are guys showing pictures of their muscles. There are more dick picks than pictures of women in any context. Most of the pics of girls showing their tits are actually trannies.
I'm not all that sure that I want to draw any conclusions from it, but I suspect that somewhere in there is contained the battle of the sexes.