if you did split the genders, there will be a small population of girls and a large clutter of guys, it's just the guy/girl ratio is higher for guys. the percentage of the girl population that plays DDR and are really good is the same percentage for the population of guys who play, for example, in UW, I've seen about 10 girls play DDR, and only 1 is very good, (Legend of max good) and about 20 guys that played, and about 2 of them I've seen beat PSMO. I'm in the category of Max 300, Paranoia survivor, and maybe max unlimited. and everything below. so it's 1/10 for girls and 2/20 for guys, that's just an example
BTW I got another question, is there going to be a stepmania setup? like TV hooked to a laptop and a dancepad to play custom songs? if there is I can bring some of the things I've made for a few anime songs. (Not likely probably ^^;)