Doug Kaye has a great post today about the "Future of Radio". One quote that stood out to me was this one:
The future of public radio may not be podcasting, but it will certainly be based on much lower-cost methods of producing and distributing most programs, and as incumbents in the industry, the WGBHs of the world are unable to cannibalize their own operations to the extent they must to survive.
I saw this first-hand when I was on John Furrier's PodTech.net show. Using a laptop, a mixing board, two mics and an iRiver, John had his own portable studio. Total cost, including the laptop, was under $6k. One (of many) reasons that podcasting has grown so rapidly; it is "open source media" at an accessible price point.