If and when this is done, it will not be done via boycotts. Rush, Hannity, et. al, are pretty well invulnerable from the usual gang of country clubbers, left wing educators, and race hustlers who are in the process of eliminating Don Imus. Imus is basically a liberal who is largely dependent upon his CBS and MSNBC network connections to stay alive. Like the Seinfeld actor Michael Richards, he is entirely a creature of the MSM and can be pulled down at will. The conservative talkers are dependent on hundreds of AM talk stations that depend on advertisers like car dealers and mortgage brokers whose audience of conservative white males would disappear overnight if there were a purge of conservatives from their stations.
What will do in conservative talk radio is a revival of the "Fairness Doctrine" that the LBJ Administration used to shut down 1960s era conservatives. I could easily see it reinstituted by a Democrat Congress with the blessing of a White House occupied by the likes of Hillary Clinton, Barack Obama, John Edwards, Rudy Giuliani, Mitt Romney, or John McCain.
....or George W. Bush............
That is why conservitive talk radio better have the satilite and internet streaming back up plan just in case.....