What is an ARG?
Definition of an Alternate Reality Game
How is it different to an Easter Egg?
Easter Egg is just a hidden part of a website, ARG makes people crack codes together, usually on and offline.
Australian ARGs happening at the moment
Gizmodo Forum Quantum Central and the Gizmodo posts
The Presets Talk like That
Well done to both Agency and Clients who did these, it takes balls!
And Kate's post on the confusion with ARGs (Nokia example)