GamePC has tested WD's new WD1500 150GB Raptor HDD and they don't just test one but four in RAID-0! Pretty expensive, considering these drives cost around $300 a piece.
One of the Raptor 150's major new features is the ability to support NCQ (Native Command Queuing) technology. NCQ, when active, allows the drive to re-order read/write commands to process them quicker, instead of processing commands in the order in which the drive received them. In theory, this should mean NCQ is faster in just about every scenario, especially during heavy multi-tasking where you're reading data off of different sectors of the hard drive. NCQ, heralded as the "next big thing" for hard drives, is suffering from a backlash of sorts recently. Many users are claiming that you can receive better performance by turning NCQ off.