We've been thinking about it for months, and now it's a reality. Using Poderator you can now publish your own video podcast that is easily viewable through iTunes.
Video podcasting is really nothing different that traditional podcasting. Instead of linking to an MP3 file, you just link to your video file. So far we can confirm that .mov files are playable in iTunes, we'll be testing others shortly. Since we don't yet have a video iPod I can't confirm whether or not the video will play directly on the iPod at this time. I've heard there is a special format "H.264 video" that the video needs to be encoded to play on the iPod. It's a simple export from QT Pro.
To see a cheesy example we've added a test clip featuring Walker Texas Ranger to my Podcast: http://seven2.net/nicks_podcast/murto.xml