There is a great group writing project just kicked off on Newbie DM. For anyone interested in writing campaign settings on professional or semi-professional basis, you must look at this project.
I will provide an empty map of a continent, and then those bloggers that wish to participate will be assigned a plot on the map, and it will be theirs to fill in, populate, and create. You’ll also know who borders your area, in case you want to communicate with them for some border issues, or other things neighbors need to work out…
Then at the end of the project, we will fill in the map with all our creations and have a fully detailed world created by the community. The time limit to create your slice of the world is yet to be determined, but it will be enough to get something going. You aren’t working on a two-week deadline here. These things take time.
For the full story: The RPG Bloggers Network Campaign Setting