Surly the demand comes from people wanting to use more computer power than they have, and that supply is met by thous with extra computer power selling there spare capacity. The medium of exchange is safecoin?
To my mind its impossible to know if they have a good economic model until we see what people do with the system, will people demand more power than they have (price goes up) or will there be more power than people demand (price goes down).
What could be done with all that processing power? unimaginably virtual worlds? Extremely cheap laptops where you pay purely for what processing power bandwidth you use.
What a great time it is to be alive and see all this unfold and evolve
If they implement bytemaster's advice:
3) charge* users any time they consume more than they produce* I think it's obvious they must charge safecoins...