Great concept, and so far it looks like the execution is really good as well. However, I agree with rnernento about the gender icons. I see how they're based on the standard male and female symbols, but it's still a bit confusing, and not even slightly intuitive to someone who's never seen them before. I'm not sure what a better clever idea would be, but perhaps it would be best to switch to a basic M and F until another idea presents itself. Confusing symbols could potentially drive people away for no good reason.