The mic passed from the don of St. Louis critics, Joe Pollack, to the inquisitive Mike Sampson on the cultural program CityScape, which plays live on Friday mornings and is rebroadcast on Sunday mornings. A grateful KWMU audience gives praise. Pollack knows his stuff but never stopped reminding his audience and his guests that he knew his stuff. What were the guests there for, other than to listen to Pollack talk? Now, Sampson knows a few things, too, but what he doesn't know, or what he thinks his audience might not know, he asks. This is novel for the radio-interview format, and impressive. Sampson's approach to hosting CityScape is to act more like ... a host. He invites interesting guests and asks them interesting questions, and the show just moves along -- until the call-ins begin, but the problematic nature of that format we'll leave for another time. Curiosity is a worthy trait in an interviewer, and Sampson has it.