you might want to check out http://said.fm/ it provides recommendations for podcasts.
We love discovering new stuff to listen to and our theme of the day is a simple showcase of this, incidentally here's a very basic RSS feed I use for testing: http://rss.said.fm/v0.1/themes/theme_of_the_day.xml - this might disappear in the long term but for now feel free plug it into ur iTunes and go!
We're finally ready to rumble again after recently running out of cash. Our next priority is to make the app mobile and very developer friendly (and slightly more fun and social). Watch this space!