The original Kinect is touted to be able to understand American Sign language, even though we have yet to see that. The device has certainly brought some fun to gaming and even some very cool hacks in the form of the self aware r/c chopper and other various devices.
Roumors abound of the Kinect 2 being able to read lips and understand facial expressions. If this is true then we are definately going to see some very cool and fun interactions with our devices, especially with the Kinect for Windows device and plans to integrate Windows Phone interactions.
Kinect 2: So Accurate It Can Lip Read? | Gizmodo Australia.