Not a one of my RL friends listens to any podcasts. It's very frustrating. I am not sure how to get them to convert (some of them don't have MP3 players which makes it challenging).
I have a couple of friends who'll listen to one if I thrust it on them, but not regularly.
One friend
really hates the slow pace of listening v. reading (which doesn't bother me, since I mostly listen while I'm driving, so I couldn't read anyway), but he's nice enough to listen to episodes that I've narrated, and often ones that I recommend if the text isn't available online somewhere.
Technology just isn't set up to support podcasting very well. You need specialized equipment to listen in the car (either a really up-to-date stereo with a USB or other flash reading port, or an AUX input) and when people aren't driving, they'd rather be watching TV (or, in the case of people like my friend, reading rather than listening).
Some people walk, I guess, but the only people I know who do that, walk with friends so they can socialize.
Can't win.