Evan Williams is one of the people that created Blogger and is now trying to do something similar for podcasting (Odeo). He explains clearly and simply why podcasting is catching on and why it is somehow more than –or at least different– than radio as I have always known it: (By way of Scripting News.)

While blogging can be about playing on a world stage to influence, gain audience, and, potentially, monetize (the same goals as most other media), there are millions of people who are happily publishing daily without those motivations. For them, it’s more about expression, self-reflection, and communication. I call these people “casual content creators.” It’s not just that they’re amateur or part of the great, unwashed, Long Tail. It’s that they’re playing a different game.