While I agree with your point, Paul, I'd have to say that many of his sketches poke fun of blacks as well. We need more like him. I feel there are very few subjects that should be taboo for comedy.
Also, the reason that it's "O.K." for blacks to poke fun of whites is that whitey has the power. You know what they say, "Black is beautiful, tan is grand, but white is the color of the big boss man."
Again I don't feel that it's not O.K. for whites to be so afraid to poke fun of other races in clean fun. I try to think globally and act locally on this with many of my friends and aquaintances of other races. I usually throw in some white humor to "keep it fair and balanced." We all do it to each other because we all know where each other's hearts are at.