@warren: I think the most valid gripe concerning aero was the speed degradation of the UI, compared to XP. Vista was just a dog, and memory footprint was horrendous. It really took WDDM 1.1, before there was significant improvements in this area.
I don't wax nostalgic for the stacking window manger. But, if you don't like the DWM, you're not going to like Windows 8. New features / bugs aside, the best thing Windows has going for it is backwards compatibility-- with the notable exception of Windows RT... Now that's a cluster F.