Engadget says...



And I say... Not likely. At least not likely what this product is indicating nor geared for.

While there's an automation profile for Zigbee, Z-wave, which is not compatible, commands the lion's share of the home automation landscape. Zigbee however is popular precisely in the market this product covers, monitoring. Zigbee equipped smart electric meters have now been around a few years, and it's why the Ecobee thermostat also supports that technology. The Nest's WiFi radio already gives it all the communication capabilities it needs to join any home automation bandwagon.

I can see Nest releasing a replacement base plate (the part that gets the wires and to which the stat attaches) with built-in Zigbee plus a firmware update for the thermostat itself to allow monitoring energy consumption from the meter and use that information and time-of-use data to better plan its heating and cooling schedules.

EDIT: The image from the FCC is labeled as "back cover" in the official document, so it looks like it may be a new Nest main unit.