As I was researching documentation hosting options within readsky, I came across quite interesting slideshare by Mikko Ohtamaa titled Write the Docs.
In this slide share there's a slide with a piece of blog note by Karl Fogel, titled Why the smart people leave a Forum. I highly recommend this note to anyone trying to find the best way to pass information about his project either to fellow programmers within company, or other programmers about his open source project.
Let me just add this, that you're obliged to leave information behind, for the case, when you're not around to answer questions. And readthedocs seems like a good option, as it provides you additionally with automated documentation build process, so you just need to keep your documentation near your code and up to date.
I always tried to follow this principle either by writing long and detailed readme for my symfony 1.4 plugins, or recently documentation those for pyramid. So reading this made me feel good about my published work.