Thunderbolt Supports External Boot Disks
Thunderbolt equipped Macs are able to boot from external Thunderbolt drives. This means that you could run a full Mac OS X, Windows, or Linux installation from an external drive connected to a Mac with Thunderbolt connectivity, and because of Thunderbolts speed, it would be extremely fast. How fast? Theoretically, Mac OS X running on an external Thunderbolt drive should be just as fast as booting from an internal drive, but using an external SSD would actually be faster than an internal spinning hard drive.
This also opens the door for further OS X dual booting options, multiple OS booting, and general ultra-fast expansion on hardware that is otherwise limited with internal expansion options. Currently, Thunderbolt comes on the MacBook Pro and iMac, but it is expected to gain further traction with inclusion on upcoming MacBook Air, Mac Mini, and Mac Pro hardware refreshes.
This was found via MacRumors, they also mention that Thunderbolt supports Target Disk Mode, an option that was otherwise limited to Firewire equipped Macs.
Update: Demonstrating the speed of Thunderbolt vs FireWire and USB 2.0 is this recent benchmark chart from MacWorld that shows off an external Thunderbolt drives incredible speeds:
Those read and write speeds are as fast if not faster than many internal SSD’s!