I have a tab for podcasts on the Media Hackers page.
The URL for the JSON river behind the podcasts tab changed, as indicated below.
New URL: http://static.scripting.com/podcastriver/River3.js
Old URL: http://static.scripting.com/houston/rivers/podcasts/River3.js
If you've got a river displayer that uses the old URL, I think you'll find there are more podcasts in the new one.