The XO laptop is back with a new look and a new design, at least in theory. Nicholas Negroponte unveiled photos of the upcoming XO-2 device this week, with an announcement that the revamped computer would be ready for delivery by 2010 and carry a price tag of $75. Gone is the green plastic keyboard, replaced instead with a second touch screen. The device can be opened to function like an electronic book, or it can be rotated to a more traditional laptop configuration, with the new screen assuming the role of virtual keyboard.