We held a mini documentation sprint this evening and tried to flesh out some of the sparse-looking Advanced Help docs. Participants included stephthegeek, Harry Slaughter, Michelle, esmerel, merlinofchaos, Randy Fay, Brent Ratliff, myself, and probably others (sorry, I lost track :\).
Here's an upload of the current state of http://typewith.me/pvyR0RWDuS where we were collaborating on this (html, renamed to .txt to appease drupal.org's filters). Please feel free to continue editing this more! Ultimately, these need to be split up into separate .html files and put into Advanced Help, which is a nice task for someone who doesn't feel comfortable writing docs but wants to see this happen.
There's also this great step-by-step tutorial about taking over the home page that Harry Slaughter is working on: http://tinyurl.com/panels-tutorial-doc