This smells like a publicity stunt from someone who sees the spotlight about to fade.
Ding ding ding! We have a winner.
And I am betting Sharpton was just drooling at this Imus thing as a chance to get lots of TV time before announcing his 2008 Presidential run. How soon until we see him, "victorious" in getting a man fired and surrounded by NYPD "because he is so important", declaring he will run for president to defeat "all the Imuses in the world!"
And the media, as you know, will be all too happy to cover it. Sharpton is not a threat to the status quo - he's a sideshow.