One of the beauties of online video are the things that you can do with it - you can overlay, link text and graphics to the timeline, create hotspots, provide interactive narratives; I could go on and on.
So, why is no one doing this ? And why does video lack the kind of social commentary you might find on text articles ? Is it because video is a didactic medium, or is it simply because this is an immature proposition ? Or is it because TV has not yet become a lean forward medium ?
To perorate and somewhat distort an idea, I suspect that McLuhan's cool medium is fast becoming a hot medium. Viewers are leaning forward and, despite its paucity, internet TV is a powerful and proven way to sell.
But the question remains - are you better off building a community site around video or a TV experience online ?