Adtron's latest solid state disk, the 160GB A25FB and I25FB, are IDE and SATA disks that are entirely made up of flash memory.
ReadyDrive, the feature Windows Vista has to optimize read/writes for flash hard disks, hasn't been talked about much. That's because other than a handful of Korean manufacturers, there hasn't been many flash or hybrid flash disks.
So we don't really know how big an improvement these flash disks will make in everyday computing, but if it's anything like ReadyBoost, then it's nothing extraordinary. But not being limited by a USB bus and having access to SATA may mean larger performance gains than we thought.