I managed to get my hands on one of these and boy is it handsome. The nest is a wifi enabled smart thermostat that is riddled with so many features you feel like you are holding a Jetsons device. Its main selling point is that it has the ability to learn. so you simply turn the thermostat and it makes a note of it, senses that you left your house and notes it, and after a week it thinks it knows enough about you to start messing with your thermostat. This is nice however, what I find fascinating is that it comes with wifi built in, and has an accompanying app allowing you to change your homes temp from anywhere in the world. Those of you who have ever left for vacation with out adjusting will see the value. Also if you have a cabin in northern USA and keep it at 50 degrees will also like entering a warm and toasty cabin.
Never think about your thermostat again.
It also looks up local weather forecast to predict energy usage, and has a neat sensor so when you approach it, it turns on. With Nest I really might save some energy this year