It's really a great product aside from the heat and power usage. Its performance is impressive and if the laws of physics would stop getting in everyone's way we would have unbelievable hardware.
It'd be disappointing to me even if the power issues and availability weren't there. It's just not enough of an improvement over the GTX 285. The Radeon HD 5870 is the same situation. I expected(Until the rumors on the GTX 480 hit, anyway) closer to a 70-80% improvement with both. I figured, since it was a new generation, we'd see these improvements, and we didn't.