I have started collecting documents about developing on PS and writing up what I have learned about the web console (quest engine).
You can find what I have collected together so far
here If anyone actually on the dev team is responsible for collecting documentation and thinks the stuff I have done is up to it, feel free to add it to whatever doc repository(s) already exist.
If you have any documents that should really be easily available to people wanting to join in on development of PS or know of any important links that I have not got in there yet, please pm me with the info.