Nice thoughts, Lee. Part of what's interesting to me about the notion of YouTube as a feeder of distributed micro-communities around specific niches is how it might also continue to serve as a platform for advertisers trying to hit the viral jackpot. While your China documentary is likely to find a much greater proportion of appreciative viewers on the chinadocumentarylovers site, its potential to become a viral phenomenon is much greater on a mass venue like YouTube.

The thing that YouTube does really well now is discoverability. You can see "best" things and "similar" things all over the place. You want to click and click and click.

As YouTube grows, discoverability of your particular kung-fu-doing teenage wannabe gangsta will be reduced, but the potential reward in terms of broad attention will also increase proportionately.

So it makes sense to me that we could see both a proliferation of niche video sites and continued growth of YouTube as a site for actually watching videos. Pretty darn interesting.