Yeah, PCI bus speed is going to be dependent on the type of bus they use. If you buy a consumer board, you're probably going to get a standard 32bit/33MHz PCI bus (AMD's 8000 chipset with the 8111 southbridge specifically states that), which is the same as current consumer boards. The 8131 chipset is a PCI-X tunnel, so you can get the higher bandwidths and compatibility with PCI 2.1 devices, but don't expect that on anything but server-intended boards for a long time.
So SATA still isn't truly going to enter the really high-end world for a while either.

We'll see it on desktop boards first, but we'll probably see those SATA-integrated chipsets before an Athlon64 is available anyway.