“The radio business may be undergoing its biggest shakeup ever. So many new digital technologies are beckoning to its traditional listeners that it’s hard to know what radio is anymore. It’s no longer limited to the airwaves, thanks to cable TV’s music offerings, the Internet, and one day, perhaps, cellphones. It’s not strictly live because online “podcasters” and others let you download music to play at your convenience. About the only thing that really separates radio listening from, say, uploading music to an iPod is that on radio, someone else plays deejay.”