I was asking myself the same question for a number of reasons lately, and here's what I have found:
As for the content, there's lots of videoblogs out there, and I will blog about that in more detail later on. As an appetizer, you can now subscribe to the new (German) Tagesschau Video Podcast (thanks Tim Pritlove).
Update 2005-11-14: Added Kitty.
Here's a bunch of smaller updates which probably don't warrant extra blog posts, but might be interesting nevertheless:
Looks like Google and Odeo are getting some competition.
Yesterday, I launched my own podcast (I had threatened to do so earlier). In an unsurpassed effort of creativity I named it Uwe Hermann's Music Podcast ;) This is a pure music podcast (no talking / ranting by me), featuring freely available (mostly Creative Commons licensed) music from various artists and various genres, see my announcement for details.
On the technical side, I have integrated the podcast into my existing website and blog (which is powered by Drupal 4.6.3). The podcasting was possible almost out-of-the-box (as most things are, if you use Drupal). I only applied this small patch which creates an <enclosure> tag for every MP3 to which I link in the respective node. I use the standard "blog" node type to create the podcast entries, put them all in the category "Uwe Hermann's Music Podcast" which I have aliased to http://www.hermann-uwe.de/podcast. The RSS feed for the podcast is simply the standard Drupal feed for that category, which I aliased to http://www.hermann-uwe.de/podcast/rss.xml. Simple, eh?
Of course, as I based the podcast on Drupal, you can comment on any podcast "show", refer to them via trackback etc. etc.
I'm eager to hear your opinions, comments and suggestions. Oh, and please feel free to suggest free music which you like. If I like it too, I'll happily play it ;)