Bottomline: If you're only looking for performance, then look no further.
The VelociRaptor series of HDDs has matured from the earlier 300 GB capacity, 16 MB cache to the newer, improved 600 GB drive. Though it still operates at 10,000 RPM spindle speed, its cache has been bumped upto 32 MB which helps faster processing as the disk does not need to keep accessing the main memory for data frequently.
The size of this 2.5 inch drive is actually 3.5 inches because of the attached heat sink (ice mount as it is referred to) which is designed to keep the drive cool even at high temperatures, the ones found in data centers. The new disk operates through the SATA 6 Gbps interface which helps faster operations.
We observed a marginal increase in the average transfer speeds of the drive as compared to the previous model in this series, reviewed in the September 2008 issue. The drive delivers 122 MB/sec with an access time of 7.2ns. The burst rates achieved by the disk are around 176 MB/sec which is a major high point in terms of performance. Overall, the improvements in the specs and performance of the VelociRaptor, make it a worthy component for enterprises.