What do you think of "Digital City Mechanics"?

Original file was here: http://builddigcity.pbworks.com/w/file/fetch/48870648/Digita...

But I wasn't sure it could handle too much traffic so copied to Google Docs.

A video summary is here: http://vimeo.com/35550899

Another PDF is here: http://www.box.com/shared/lmkgf4qsztc0k9qboji1