If you're thinking of building your own Vista machine, Asus has four new motherboards for you to optimize your Windows experience. Two of them are for Athlon 64s and the other two are for Intel Core 2 Quad processors. All of them have a flash cache that works with Vista ReadyBoost to boot faster.
The two pricier models have a Asus ScreenDuo, which means it supports a secondary display connected by USB that runs its own OS off of Vista's SideShow features. Presumably these boards will have Vista-ready drivers, which is nice, so you won't have to dig around for hours on the internet (not on Asus's own site, mind you) to get your audio to work. That was fun.
Asus Announces Vista-Optimized Motherboards [Extremetech]