I've spent some time in one of these in a Google building and it is extremely cool. Each panel is hooked up to a relatively low-powered standard machine running Google Earth on a stripped-down Ubuntu release. From what I could surmise (and based on how I saw the system loading/caching data) each machine spoke on a network and had a differently-set camera view slaved off the center machine. The input device (in my case it was a 6-DOF joystick) is connected to the center machine.
Also, it got extremely warm in the room after a few minutes of usage. Plasma screen backlights + hot graphics cards = quick increase in temp.
Also, it got extremely warm in the room after a few minutes of usage. Plasma screen backlights + hot graphics cards = quick increase in temp.