I had read news that Nest was probably going to release something in this segment of the market. Given that we are mere weeks away from moving into our new home, and I'm planning two install two Nest Thermostats as it is, the announcement from Nest this morning has me very excited.

Nest Protect

Safety shouldn't be annoying. The Nest Protect smoke and carbon monoxide (CO) alarm quiets down when you wave - no more swinging towels or brooms - and messages your phone when its batteries run low. Nest Protect speaks with a human voice, telling you where and what the danger is, and gives you a friendly Heads-Up before turning on a loud alarm.

A few points that I found interesting:

They have both battery and wired versions
If you also have Nest Thermostats, the Nest Protects will share information with them.
Information shared can do things like turn off the furnace if it detects CO2, or motion data to assist with Nests learning.
Sends data to its iOS application
You can wave your hand near the Protect to signal for it to turn off in the event the smoke is from a source you're aware of.
At night, it can emit low light based on its motion sensor to help light the room in the event the lights are out (presumably so you don't trip over things on your way to the bathroom in the middle of the night without having to wake up your spouse.).