I asked this same question over in the
Chicago Podcast Meetup bulletin board.
You don't need iTunes to listen to podcasts (although it's my favorite program to use for this). There are many other programs you can use to subscribe to podcasts. Here's a list:
http://www.podcastalley.com/forum/forumdisplay.php?f=258
It's a nice list, cuz it tells you which programs are more popular by page views.
And I'll give my list of five recommended mainstream podcasts, but with links to their info page, and a link to their feed. When you download a podcasting program other than iTunes, you paste in the feed url to subscribe to the podcast.
Slate Magazine Daily Podcast
info:
http://www.slate.com/id/2119317/
feed:
http://www.slate.com/podcast/
Bernie DKoven, funsmith
info:
http://www.deepfun.com
feed:
http://feeds.feedburner.com/Funlog
Walk in the Word with James MacDonald
info:
http://www.walkintheword.com/Broadcast_Podcast.aspx
feed:
http://www.walkintheword.com/podcast.xml
The Accidental Creative
info:
http://www.accidentalcreative.com/
feed:
http://www.accidentalcreative.com/ac-feed.xml
NPR: Story of the Day
info:
http://www.npr.org/rss/podcast/podcast_detail.php?siteId=4819386
feed:
http://www.npr.org/rss/podcast.php?id=1090