My understanding is that it's around Virtual Currency trying to monetize your applications (facebook, myspace, etc). And you still monetize a 'user' as you make him buy Virtual Currency via either

i) Real Dollars. (you get the money)

ii) Doing Offers. (The Offering company pays you)

Many VC's think it's a proven model for at least Social Networking Applications. (See Offerpal Media, Peanut Labs)

I will be heading there tomorrow, so I will update you guys how it went.