Living in the iPod age has made me very familiar with podcasts. As I think I've said before on the discussion board, it's come to the point where I prefer to listen to "Wait, Wait...Don't Tell Me" or "This American Life" over music.
Looking through podcastalley.com I find a lot of podcasts that I would be interested in listening to such as "The Signal" which talks about the Joss Whedon's Firefly and Serenity, and maybe "Mail Order Zombie" which reviews all the straight-to-DVD zombie films that are produced.
Browsing through the most popular podcasts, I didn't find many that were directly, or indirectly, library related. There were, however, a good deal dedicated to comic books. As graphic novels rapidly become the material used for successful movies, I think that they also deserve a lot of attention from libraries, especially public libraries, because this is the medium of literature that the young generation seems to enjoy. There are, of course, many podcasts like "The Book Report" which are sort of book clubs--often with live interactive discussions.