David Mitchell is very funny anyway, but I thought this article was quite perceptive as well:
"Wikipedia's level of accuracy is remarkable considering its eclectic provenance. And second, readers should always question the veracity of what they read and the motives of whoever wrote it, and in the internet age more than ever. People who allow themselves to be made credulous by stylish typesetting and a serif font are screwed. And if Wikipedia, while being very informative in most cases, teaches a few lessons about questioning sources, then that's all to the good."