http://jameswharris.wordpress.com/2008/04/19/electric-cars-and-wikipedia/
(and here I repeat myself)
Wikipedia gained its present hideous popularity through convenience - an encyclopedia with a ridiculously wide topic range, with content good enough to be useful no matter how often we stress it's not "reliable" (certified checked) as such.
Britannica and Brockhaus may be theoretically higher quality, but are not right there on everyone's desktop - they fail on practical availability. Worse is better. Most of Wikipedia's readers (the people who make it #9 site in the world) wouldn't have opened a paper encyclopedia since high school. Wikipedia fills a niche that was previously ignored when not botched.
So the paper encyclopedias put their content online. Can they provide a better website than Wikipedia? Ignoring the process, just looking at the resulting body of text? Can they produce content on the range of topics people look for on Wikipedia fast enough at their advertised quality level and keep it up to date? To what extent can they compete with Wikipedia without becoming Wikipedia? What would that entail?
"Really, I'm not out to destroy Microsoft. That will just be a completely unintentional side effect."
- d.