Jon Hamm, Ashton Kutcher, The Dictator: Is Racially Charged Comedy Ever OK?

Now that Ashton Kutcher's racist PopChips ad has been pulled, I've gotten to wondering: Is doing racially charged comedy, such as blackface, ever OK?
 —Vegas is...

Source: http://feeds.eonline.com/~r/eonline/answer/~3/mT61eET2Ki0/313734

Dominique Swain Donna Feldman Drea de Matteo Drew Barrymore Ehrinn Cummings