Radio UserLand and Podcasting
We're working additions to Radio's RSS publishing to support Apple's "extensions" and podcasting in parallel with another project and hope to have an update soon. There's a callback structure that the script at radio.weblog.writeRss that can be used. When the script runs, it looks in a table for scripts to run in callback tables at the start and end of publishing. Ideally, your changes would go in a script in the callback table--that's where we'll put ours.
This function is part of a larger initiative to create a dedicated "podcast" category in Radio, allowing new users an easier path to create RSS feeds and publish them to the web. I'll make sure to add a pref to the category page with a description like "Enable iTunes podcasting extenstions to this RSS feed?" so existing categories will work fine.
Finally, I'll be writing the definitive "How to podcast with Radio" next week to go with these new changes.