Francois, thanks a lot for the link to Super. It looks great & I'll definitely be using it in the future.
The question of video formats w/ regard to our podcast is moot however. Because some people experienced problems when trying to download the audio podcast, I've decided not to host the video source file internally, but to let Vimeo do that for us. You can upload many different video formats to Vimeo & they convert it for streaming purposes (via either Flash or, more recently, native HTML 5). They leave your original file for a week and include a download link to it. After a week they re-encode the file as an MP4 (smaller) and delete your original. In other words, it doesn't really matter what format I save my original as.
Because the original link is only for a week there's no point inlcuding it in our feeds and anyway, the WMV is too big at around 370MB to expect most people to download it to their computers/phones/media players.