That question was posed on a recent forum entry at Podcast Alley and I thought I would share it with those of you who are not podcasting nuts and therefor do not hang out in podcasting forums.
Here is my take on videocasting or videoblogging.
It will eventually be the future, but we are talking a long way down the road. The barrier to entry is still way too high. Storage of video files makes podcast audio storage look insignificant. Also, the tools are just not as user friendly as with audio.
I do video production for a living and short of those little video diary segments you see in all the reality shows, it takes quite a bit to turn out a quality video project. When we film a corporate seminar or speech, the editing is usually a four to one ratio of footage shot. (I.e. when we shoot an hour, it takes four hours to edit it into a broadcast quality output.)
I do think it will eventually happen, just not real soon.