I've seen this argument too. Somehow Chris Tucker and Dave Chapelle are victimizing white people because they
make racial jokes in their acts.
1. Don Imus used a racial slur to attack innocent young women.
2. Chris Tucker uses racial stuff for a cheap laugh in the midst of a comic routine. He also jokes about black people.
3. Dave Chapelle (and Chris Rock) use racial jokes in their acts not cheaply but to make social commentary about all the races. They're not throwing out cheap attacks, but instead using humor to talk about race relations in America.
4. Anyone who thinks that these comic acts are the same as Imus (or others, like Rush Limbaugh) just dropping racial bombs all over the place is just the end product of a life of stupidity where you really believe the stuff peddled by the right that the only really oppressed people in the world are white christian conservative men.
If you believe this, you are stupid.