"In its hour-long Xbox One presentation, Microsoft blazed through announcements for its new next-generation console, including one ostensibly important feature that may raise some eyebrows: the new Xbox will always be listening to you, even when it's turned off.
The reason for always-on listening mode is simple; Microsoft wants the new Xbox to respond quickly and naturally to you, whenever you need it. To fulfill that goal, the company will ship the new Kinect — its motion-sensing and listening peripheral — with every Xbox One. The new console uses the new Kinect for just about everything: switching between games, movies, web browsing, and live television, all of which can be done with voice commands. (In fact, the new console needs the Kinect to operate at all — it's not an optional add-on like with the Xbox 360.) Even when the console's turned off, users can simply say "Xbox On" to power up — which means the new Kinect will be listening to you in your living room at all times."