Two design podcasts I find constantly informative are Design Matters, by Debbie Millman; and Icon-o-Cast, by Lunar Design. Both have more than a little to say about experience design, though their ambits are quite a bit broader.
The podcasts display distinctly different temperaments, probably geographic in origin: Millman's attitude is alternately reflective and in your face, as befits a New Yorker; the Lunar Design team is San Francisco Bay laidback, "Wazzup?" all the way.
Millman takes a critical approach to design: in a quiet place, she interviews designers, brand managers, etc., inquisitively. She also voices her own opinions. She's a writer/critic/design aficionado whose first-person style conforms easily to the podcast's conversational format. The Lunar approach is more sitting-around-the-bar style, or in the field. It's more often breathless, although the Lunar designer/reporters are not afraid to call it as they see it.
Lunar Design's John Downing, Dan Senatore, Max Yoshimoto and others are more technology/product oriented: they favor first-person reports from within Lunar and interviewing with other companies' representatives.
The knowing crone and the young hunters: the latter are hip to changes on the design landscape, the former divines deeper meanings. Try 'em both. Design Matters is available as a stream via Sterling Brands or you can do a search for it on Apple's iTunes. You can subscribe to Icon-o-Cast from the Icon-o-Cast Podcast website and also via iTunes. They're now among our links.