MS developer: Vista is an incremental improvement
I came across this on Scoble's blog, a video he made a while ago of a visit to the team handling Vista's audio and video drivers.
While much of it is composed of talk on DRM (nothing new at all, apart from the team leader coming up with some hokey Web 2.0 piffle), if you skip to around 2/3rds of the way through they talk about the way multimedia is streamed in the new kernel. After the demo the team leader makes an interesting comment about Vista: it has a lot of incremental improvements made possible by the ground-up rewrite that add up to a lot in the end.
He says you can't put that on the box as a bullet-point, but TBH this is the only pro-Vista argument that gives me any desire to buy the OS when it comes out.