SATA is still slower than SCSI, interface wise.
Typically, SCSI hard drives are made for servers and high end workstations and have 10,000 or 15,000 RPM speeds. The other nice thing abotu SCSI is you can daisy chain up to 16? drives together. The downside of SCSI is price. The SCSI interface is 320 or 640 MBPS.
The ATA interface is the most common. Virtually every mothherboard supports ATA 66, ATA 100, or ATA 133 drives, with ATA 100 being the most common. It's cheap, and most of the ATA drives are 7200RPM.
The SATA interface is a new replacement for the ATA interface. Their is no real peformance difference with 7200 RPM drives however, and thats virtually all what runs on this interface besides the 10,000 RPM raptors.
For the fastest hard drives possible, I recomend the 15,000 RPM Seagate Cheetah series.
http://www.newegg.com/Product/Produ...Ntk=all&N=0&minPrice=&maxPrice=&Go.x=0&Go.y=0