It may be that this Encyclopedia was foreseen by H. G. Wells who wrote about a World Brain:
The Idea of a Permanent World Encyclopaedia - H.G. Wells Contribution to the new Encyclopédie Française, August, 1937 http://sherlock.berkeley.edu/wells/world_brain.html
World Brain is the title of a book with several essays by H. G. Wells.
(When was this first published?)
A new edition of World Brain : H. G. Wells on the future of world education was published in London by Adamantine Press in 1994, ISBN:0-7449-0114-6
Among the essays, one titled The Idea of a Permanent World Encyclopedia is remarkable in suggesting a vision very similar to Wikipedia. This essay first appeared in the new Encyclopédie Française, August, 1937, and has been made available online as part of Karl-Erik Tallmo's ArtBin webzine.
