The mix at DragonCon is split 50/50 or so on m/f grounds, but whites far outnumber blacks, however, those blacks in attendance are generally welcomed. In fact, there’s one black guy who shows up dressed as Blade every year, who looks very convincing, and the chicks are all over him without fail. I’ll bet he doesn’t get a lot of sleep during the Con. Asians and Latinos show up too, but I really have no idea how many, as with so many folks in costume, most don’t really “stand out” if you know what I mean.