On March 5th this year, ARG designer Adrian Hon presented to Google on ‘How to Make an Alternate Reality Game, Or, Perplex City: A Look Behind the Scenes’. His abstract: 

Alternate Reality Games not only exist on the web – they call you up, invade your TV show and fly helicopters outside of your house. This talk will provide a quick introduction in ARGs, and focus on how we’re using lessons learned from Perplex City Season 1 to make Season 2 a much more fun, more accessible and more immersive experience. 

Thanks to Google, here is the video!: