Day 3 of the conference is Hackathon day. It's a day where everyone can try to develop game for each other's platform/techonology. Today is more of an experiment, to see whether or not companies are interested in this sort of idea.
I only stayed for about 2 hours since my flight back to Redmond is at noon. However, according to Jeremy there weren't that many attendee since most people already got what they needed from day 1 and 2. At least now we know that we don't have to do the Hackathon day for next year's conference.