FYI, this book has been getting attention lately, so you may want to take a look:
The Wisdom of Crowds: Why the Many Are Smarter Than the Few and How Collective Wisdom Shapes Business, Economies, Societies and Nations by James Surowiecki
To Wikipedians, this merely reinforces what we've all know and have experienced firsthand. But it is interesting that the theme of the "power of many" is being picked up by the mainstream and it may prove a useful reference for folks who just "don't get wiki." It's a more general book than Rheingold's "Smart Mobs," which could be dismissed as too technocentric and focusing on mobile devices
Instead, Surowiecki's "Wise crowds" are described as having (1) diversity of opinion; (2) independence of members from one another; (3) decentralization; and (4) a good method for aggregating opinions. (four points quoted from Amazon.com's review).
I'm sure Wikipedians will find these concepts quite familiar.