The ambiguous corners belong to the serious black thinkers such as Thomas Sowell and the white comedians such as this Don Imus radio fellow who is being condemned by Al Sharpton, arbiter of all that is right and holy.
You'll notice that The Simpsons are totally terrified of anything having to say about blacks. The show has a completely stereotypical Asian Indian, Apu, but no continuing characters who act recognizably black. The upper-middle class Dr. Hibbert is a parody of Bill Cosby's Dr. Huxtable character, not of a real black. Meanwhile, the show's creators telegraph to viewers that they are avoiding joking about blacks by creating two black characters who behave indistinguishably from their white partners. There are Homer's co-workers Lenny and Carl; and there are the cops Lou and Eddie. After 15 years of watching, I still have no idea whether it's Lenny who is black, or if it's Carl. The same goes for Lou and Eddie. If there was just one ambiguous duo like this, it might be an accident, but having two pairs indicates the writers are making a joke about their pusillanimity in the face of race.
Imus doesn't show this caution, so, either now or later, he will likely go the way of most such white males as they age and get crotchetier and lose their self-control. Eventually, he'll say something and the Great and Good will turn on him. I was happy that the magnificent Chicago columnist Mike Royko had the good fortune to drop dead of a heart attack at around 65, while still on top. He was a curmudgeon and a drinker, so his eventual humiliation over saying something politically incorrect was inevitable if he had lived long enough.