Why, what grand purpose does it solve today? Switchers? No, the cost of a new monitor, keyboard and mouse is trivial now. Apple's not even running switcher ads anymore. Hobbyist? No, you can't upgrade anything in the box anymore. Server? Maybe, but if Apple really cared they wouldn't put the power supply inside the box. Home Video? No, Apple will have a better solution for that very soon. Car? No, better solutions exist from practically everyone.