I think that dividing lines like race may be obscured by the fact that a) we all participate in and appreciate a culture that is predominantly black and b) often try not to alienate ourselves by adopting a style that fits in somewhat (although there are those that clearly don't).
I find it fairly hard to distinguish black vs. white vs. asian vs latino vs..., especially combined with different languages, locations, ages, genders, etc, but the differences can sometimes be pinpointed.
Just ask a question like 'Does race on OKP matter', generally those that claim it doesn't and don't shout out their skin colour are white. I don't know if this is the right place to get into the reasons for that though.
Good luck,
-B

"I go to work in the morning and people give me shit. That's how I know my day has started."-Kids in the Hall