Approximating 350 MHash per GPU works out about 15,000 GPU's for the network's ~5 THash/s ... so actually an overstatement.
350 MHash per GPU average? Perhaps you could re-calibrate including the nvidia vs Ati market share ^^
your figure is not so much off anyway, still I think it's quite a big number... when you say "nothing compared to everyday stuff", well, I think there's a bit more than what you think... it's a geeky thing but it's still impressive!
Yes, impressive for the computer power of the network. I'm kind of annoyed there hasn't been a slashdot article on the technical network aspect achievement alone. If nothing else it has wiped folding@home's bottom, and the hardware come together in not much more than 8 months.
In the bigger scheme power usage and hardware in the industrial sphere it is nothing. A small fraction of the gaming market or Xbox network power consumption and hardware probably even.