There was an excellent tribute to Pryor in today's St. Paul Pioneer Press. An excerpt:

I've heard it said that the definition of greatness is when everything that came before you becomes obsolete and everything after bears your mark. That was Pryor. After him, Milton Berle and Bob Hope could never again seem quite as amusing. And virtually every comedian who followed — Murphy, Chappelle, Letterman, Rock, Hughley, Williams — bears his mark.