I'll give Credit to TechLEARNing.com, which you should visit, before linking directly to the site below. This is a good high level overview for educators to understand what "podcasting" means, how the process works, and what value it offers to education.
In my own blogging, I've often considered podcasting, netcasting, vidcasting, webcasting, etc. Essentially all the same, just many different ways to say posting an audio or audio/video recording via RSS feed. I'm particularly thinking about whether I should start looking for LiveMeeting presentations that our field in the Education vertical are recording and possibly posting them in Soapbox for public archival and feed-based aggregation.
What topics would be most valuable to EDU?