Nick Carr has a good article out, looking at the concentration of views on the web. In some ways I agree with Nick, especially when he notes:
In the end, though, the internet seems to be following the same pattern that has always characterised popular media. A few huge outlets come to dominate readership and viewership and smaller, more specialised ones are consigned to the periphery. Most of the largest sites are now in the midst of acquisition sprees or expansion programs intended to extend their dominion. Just last week, MySpace announced it would buy Photobucket, the largest photo-sharing site; Facebook said it would expand into the classified advertising business; and Google chief executive Eric Schmidt said that his company has been acquiring small companies at the rate of one a week to build out its portfolio.
The difference remains the cost of entry. Today, it is still not just possible but probable that a single person or small company can develop a property that becomes an authority in quick order. Look at TechCrunch, the FakeSteve blog, twitter, for recent examples.
So the big may get bigger, but I think they'll keep hearing the competition coming....