RPG Psychic World Project

In creating the RPG Silver Cord, I need to fully develop the gaming world, or in this case the unseen world, to reflect the setting I'm trying impress upon players and GMs. I want it to be developed enough that GMs don't have to do a lot of background work, but I don't want it to be too strict that nothing but cannon events can happen.

There is a game that was posted by Neel Krishnaswami on November 20, 2003
http://www.20by20room.com/2003/11/lexicon_an_rpg.html
It's called Lexicon: an RPG. Players take turns writing a scholarly encyclopedia article on a fictitious topic. Everyone starts with the letter A and then moves to the next letter until you get to Z. There are rules for referencing articles called phantom entries, and that an author is not to cite their own work. Then at the end, folks go back and fill in references they missed in the first pass.

Neel's blog gets a lot of feedback, and apparently players have a blast doing it.

I'm thinking of setting one up for the world of Silver Cord. I don't know how much interest people have in a world building game set in the secret world of modern psychics and the organizations that hunt them.