In general I think the video adds nothing to the Mixergy interviews -- I wish there were a way to subscribe to mp3 only.
Some kind of interview + screencast/demo would be vastly more interesting, but harder or impossible to do live.
I also appreciate the snowball microphone Andrew bought, and wish his guests had similar quality setups (a few have, many have not). It would also be nice to use a better audio codec and better buffering.