It sounds like they are actually trying to throw in some 'entertainment'/gamification features, according to the Wired article (http://www.wired.com/gadgetlab/2011/10/nest_thermostat/), such as a leaf icon (achievement badge) that shows up when you've set the temp to something eco-friendly. There's also a lot of potential with the web/mobile app, where system monitoring can be done in some interesting and interactive ways. I hate to bring in the cliches, but this actually has potential to have some kind of social media integration. A significant minority of people love keeping track of the personal data of their lives, and this can be another platform for exactly that.