[Update 8-6-07: I've updated the wikipedia contributor map based on my recent discoveries. Please see this post for a better contributor map. ]
Here are some interesting factoids culled from Wikipedia contributor statistics.
Compare the population of world countries to the Wikipedia contributors. In the hierarchy of users the vast majority of visitors to Wikipedia, 48 million of them, are readers; for the most part they don’t edit articles. Next are the regular contributors who contribute between 5 and 100 times per month. There are about 77,000 of those. Finally, there are the 10,000 anchor contributers (I’ve borrowed this phrase from retail marketing) who contribute more than 100 times per month.
So if Wikipedia readers are like China, then the regular contributors are like Macedonia and the anchor contributors are like the Barbados. To extend this analogy to absurd extremes, Barbados and Macedonia do all of the work, have the highest GDP and provide humanitarian aid to China!