I've started a series of commentaries with the progressive podcast. You can learn more here:
http://feeds.feedburner.com/PrgrssvntnPodcast. You can use streaming audio, or download it to your mp3 player. Also, check out odeo.com. It's a cool service you can use to find new podcasts. I'm hoping to get on iTunes soon for all of you iTunes people. I welcome your comments and suggestions!