The TechReport posted an extensive review of the Seagate's Barracuda 7200.12 hard drive. Here's a bit:

Seagate's high-density 500GB platters deliver on much of their performance potential, at least when it comes to peak sustained throughput. However, the drive's transfer rates in real-world file operations are mixed. The 7200.12 is very fast when it comes to real-world reads, but it's much slower than the competition when writing and copying files.

Flashes of brilliance followed by otherwise dismal performance is sort of a theme for the new 'cuda. The drive fared better than any other in our iPEAK multitasking tests, but it stumbled spectacularly when faced with multi-user IOMeter loads. And at more than 17ms, the 7200.12's random access time is slower than, well, any other desktop drive we've tested. Ever. What's worse, there's no way for users to defy Seagate's factory programming and shift the drive out of its noise-optimized "quiet" seek mode.

With its performance all over the map, the Barracuda 7200.12 is difficult to recommend to enthusiasts looking for a speedy system drive. However, near-silent noise levels and low power consumption do make it an attractive option for quiet desktops and home theater PCs.