I have been listening nonstop to the Bat Segundo Show. It has forced me to use iTunes, which is retarded, but simple minded. Just click, click and there are a million book podcasts to have.
Anyway, I've especially enjoyed Matt's interviews with Daniel Handler, Alison Bechdel, Gwenda Bond and Jeffrey Ford. Matt goes very deeply into plots, themes and other details of the author's work, so it may be better to have read the books they discuss, but since I have read very few of the books he talks about, listening makes me smarter.
One thing I find so compelling about these podcasts are how they wander from topic to topic and really allow for digression and repetition. After listening to one, I usually feel like I've met the author which doesn't happen when I read a tightly edited magazine profile, no matter how detailed.
Get them all, and don't be turned off by the silly intros.