I'm all about equal opportunity when it comes joking and ripping on people. I rip on myself far more than others. I think with defining "Blatant racism", it's more of a situation where you have to say, "I can't define it, but I damn sure know it when I see it." It should be blatantly obvious the difference between "That damn black" and "Yo, my niggah". Playing off and having fun with cultural traits and stereotypes should be perfectly acceptable with regard to any race. I hate to admit it, but Chapelle is the perfect example. He took it to that level very few would have ever gone in that forum, and it shouldn't be acceptable or okay to laugh at just because it was a black man doing it. It was funny...period.
I personally find a double standard equally offensive as flat out racism.