The >podcasting meme is spreading like wildfire and that's good. I imagine that the iPodder software floating around will become a bit like a TiVo, service schedules, content "channels" and more. Directory services are lacking--Dave Winer had a subsection of weblogs.com for audio posts at one time--so we need a technology to step up in stick a flag in the ground. I'm voting for RSS/OPML. It's a natural and easy to generate and it's lightweight and powerful (like an iPod).
Content generation tools are barely past the sticks and rocks stage, but moving rapidly forward. The killer app will be a software audio router that does a good bit for you, walking you through the process. There will be themes, presets for the software that optimize the apps settings: talk show, soliloquy, radio show, etc. It will also generate 30 second previews for the store (see below) or the preview can be replaced by an ad (for sponsored content) or a self-description by the author. Combine Skype, iPodder and an audio router/multiplexer and you see what I mean.
Personally, I'm ready to pay for a product using the iPodder codebase that's well executed, will deliver content to iTunes and has it's directory built in. I want to be able to shop the podcasts like the iTunes music store, that is, get a 30 second preview of content before I subscribe.
Like Russ mentioned, moblie phones need to be able to party with developers and the audio quality might not be there yet easily. A version of iPodder for the SymbianOS phones seems trivial (I am not a programmer, hence everthing is easy) and inevitable.
In summary, I'm waving my money in the air for this--who's going to take it?
Update: Dave Winer pointed to the Wikipedia entry for podcasting, so I updated my link above.