"Part of Steve Seow's job on the Surface team is understanding how people use and interact with the Surface computer - from dragging things around to pressing buttons and more. They gather a tremendous amount of data that helps them improve the overall experience and in the end impacts what we all see, touch, and sync.
Checkout this video from inside their usability testing lab. You'll also see how the Surface team uses Toshiba M700 Tablet PCs to assist them in the testing process.
You'll have to excuse the shakiness of this video - I didn't have my tripod with me." (Continued via GottaBeMobile, Rob Bushway) [Usability Resources]