The rich plankton of pop heroes and pop villains on which we Americans are accustomed to feed, the daily media soup of sports figures, ax murderers, politicians, and rock singers, the ever-running river of celebs, heavies, and oddballs that we use to spice up our own relatively humdrum lives has of late become a very watery gruel. Where have all the good guys and bad guys gone? Why does everyone out there look so gray?