Moto X follows Xbox One, always listens to voice commands
 

"The Moto X is apparently always listening for commands, the initiating command appears to be 'Ok Google Now' without having to load Google Now or select voice operation, after hearing this command the phone instantly responds with the information you require or performs the function you want, like providing directions or setting reminders or other Google Now functions." Google always listening in? Sure, that's not creepy at all or anything.

http://osnews.com/story/27187/Moto_X...ice_co mmands