In case you haven’t heard (and you probably have) steam has a “big picture mode” for people using TV’s to game on.
So far it’s been very easy to understand. Unlike metro, it isn’t shoved in your face upon launch. Also the interface is pretty straight forward even for a beta. You can even type to your friends using a controller!
Not something I would use everyday (I game on a regular large monitor) but still a very nice option.