But the prices haven't been going up by multiples of 6 for the past few years. Things are actually changing now. I don't think it's over, but in the short term, it's going to be considerably more expensive.
I don't think that's true. Vista was so hated, that 7 was pretty much universally heralded as a big improvement, even if half of that was the ecosystem getting used to the new driver model introduced by Vista.
And as others have observed, 2000 was an immediate hit with everyone who tried it.