Western Digital introduced a My Book Studio Edition II with 3TB drives for professionals who deal with hefty video and photo files. The WDH2Q60000 offers up to 6TB of space courtesy of two 3TB Caviar Green drives, which can be configured in your preferred RAID mode including RAID 0, 1, 5 and 10. It the same footprint as less capacious models (6.54 H x 3.87 W x 6.06 D inches). There's no sign of USB 3.0 or Thunderbolt, but it comes with USB 2.0, FireWire 800 and eSATA connectivity.
The front of My Book Studio Edition II has a slick capacity gauge and the device supports automatic backups via WD's supplied software as well as Apple's Time Machine utility. The unit's product page says it comes formatted for Macs, so Windows users will have to reformat it straight out of the box. You'll also need Windows Vista/7 or Mac OS X 10.5.2+/10.6.x to take advantage of the full 6TB. Pricing is set at $550 or about $200 more than buying two of WD's 3TB drives separately.