I have found another little quirk in my Zune 80 MP3 player and the way that it handles mixed (audio and Video) podcasts.
It appears that if you have a single podcast feed that contains both audio files and video files, when they are synced to the Zune, although the podcasts show up under both Audio and Video on the player, only the audio files are visible and available to play. If you remove all of the audio files (listen to them) then the videos are available until the next audio file is there.
My iPod touch works in a similar way via the podcast menu, however at least video podcasts are available via the video menu. Not so with the Zune. This is another little knock against the player that does not effect everyone. I will look to see if a solution is out there on some forums somewhere.
I should be getting my 8 GB Zune player today so look for a review of that unit coming soon.