I found the Fall 2007 Arbitron ratings for the Washington, DC market an intersting sidebar to the WGMS story, and the plans to turn it into a sports/talk station. According to that list, WGMS was #11 with 3.1 percent of the market (the top station had just double that). The highest sports/talk station on the list, WETM had 1.1 -- a third of the classical station's audience. And the Red Zebra sports/talk station had 0.7. Public radio stations don't show up in the official Arbitron rankings. The best I could find was a citation in Current that in 2005 WETA was around 2 percent.
So WGMS has a healthy 3.1 percent of the market. Dan Snyder wanted to buy it to convert it to sports/talk -- a format that pulls a combined pull of 1.7 percent of the market between two stations, or about half the audience size of WGMS. And WETA, which seems in no hurry to return to classical, sticks by their assertion that they went to news/talk to serve a wider audience -- an audience that seems at best to be roughly two-thirds the size of WGMS's classical listenership.
Is this making any sense?