I listen to podcasts all the time. Especially on the métro and walking through town, I can catch up on news, be informed or inspired or made to laugh at inappropriate times. At the moment I'm walking for about an hour every morning at sunrise (more on that in a later post), so usually listen to at least one episode first thing each day.
From a photography perspective, these are my current favourites:
Scott Kelby leads an informal weekly show, often with excellent guests such as Joe McNally or Peter Hurley. It's lighthearted and fun, but often offers useful tips. Some of the photo-critique shows are especially good.
Hosted by Frederick van Johnson, TWiP is a show based on discussion with guests in a Google Hangout. It follows a consistent format, including a discussion on a few topics of photography news, a question from a listener, and a new recommendation from Frederick and each of the guests. Sometimes there will be an interview with a key industry personality. It's informal with quality guests and often some excellent thoughts and recommendations.
Ibarionex Perello must have one of the greatest sounding names in photography. His interviews are more serious and more in-depth than the others I've listed, with a noticeable emphasis on art and vision over gear and technology. It's thoughtfully put together, with insights into the views and experiences of many great photographers. Highly recommended.
Those are where I go first, but I don't always want to be hearing about the photography industry, past or present. Many other podcasts can be equally relevant or entertaining, and these are top of my other subscriptions:
Entrepreneur and author, Tim Ferriss is often described as a life hacker. Fascinated by living more effectively or efficiently, he interview others who have succeeded in a given field to discuss their methods and philosophies. He asks some excellent questions and conveys a genuine desire to learn from his guests.
Comedian Greg Proops (from Whose Line Is It Anyway) turns his live stand-up gigs into a regular podcast. I started listening after going to one of his gigs in Paris and loved his vodka-inspired introductory monologue and frequent film and music references. He later goes into a self-confessed 'boring preachy bit' with his own take on current issues.
The inspiring, challenging talk series is available as a video series. You never know what you're going to get, but the standard is high and usually thought-provoking. It's fun to be challenged or informed on a completely new topic each time.
So those are my current favourites. Just be careful with the video editions, they can tend to fill up your phone pretty quickly. Any key shows I'm missing, especially photography stuff? Let me know.