The new MacBook Pro comes in three flavors: two 13-inch models and a 15-incher. They all have thinner bodies, better screens, and trackpads so big they blot out the sun. And you can buy it in space gray. But the important addition is the Touch Bar. This capacitive strip of OLED glass above the keyboard is supposed to change everything, again, about how you use your laptop. "For 25 years," Tim Cook said while unveiling the device, "we've been defining and redefining what a not