The official Moodle MOOC at learn.Moodle.net is now open for enrollment in advance of the 9/1 start date. Only 10 days remain to sign up on the site. Additionally you can RSVP a little more publicly via the Google+ invitation at this URL: https://plus.google.com/events/cfe14d3qijm6agirplg78s7oto8.
Spread the word, sign up and get ready. As of 8/20 around 500 participants have already registered.