According to ZDnet they are using two GTX580 GPUs, probably underclocked. I quite surpised that it's able to get all it's power from just two 8pin connectors.
ye. not for most enthusiasts i tink. they should do an extreme dual design. massive cooler, 4 power sockets + 1 for power phases stuff and summin einstein-y. summin that'd need a chop-stick as a prop