Interesting data point
I was at my local comic shop picking up my weekly fix (for those who care, Alan Moore's Promethea was the only thing on my shelf this week). The shop owner had the radio turned on when a commercial came on that openly decried the Bush administrations attempts to censor Howard Stern. It included an appeal to listeners to get out there and stop them before they stopped Howard.
This advertisement was NOT during the Stern show itself.
So, the word is not only getting out to Howard's ~15 million listeners but also to a significant chunk of people who happen to listen to some of the radio stations that broadcast Stern (unfortunately, I didn't catch which station the owner was listening to).
Just thought you'd like to know.