Another test, that has been talked about by Netapp before but which Dave didn't mention, is in-house production testing. Almost every new software release, hardware model, and new feature (like ATM) gets time in production use in Netapp's own "Real World" corporate network, often within Engineering itself. While not specifically a QA function, Netapp does integrate it's own products into their infrastructure as best as possible and such rollouts have proven to be very fruitful at identifying problems and correcting them before they reach the customers.
Bruce