In this review, they show that, at load, the GeForce 8800 uses less power than some single-card solutions out there; but I am not blind, and do see that it is using the same amount of power as some Sli and Crossfire solutions as well.
And i still think it's pretty cool, as a single card, that it beats out Sli and crossfire systems in some performance tests, like GRAW and Oblivion, all while having very nice AF at the default level, and even better as you turn the AF up.