Just tossing my two cents in here, but documentation (especially that of experimental features) is really important and can make a huge difference. Django actually had http://www.djangobook.com/en/2.0/ which was pretty cool, but they haven't maintained it. It gives you two versions, a stable book, and an always changing book. Each section of the book can have comments added to it, which an editor later goes back to review and add it to the documentation if needed.
Maybe web2py could benefit from something like this.
