I've been waiting for this, being able to ask siri(Cortana) to set my nest or lock unlock the Lockitron would be awesome. Even better would be an IFTTT app that could run certain scripts based on certain phrases. Like "Good Night Cortana" would adjust my thermostat, lock the doors, and turn off any lights that are still on and make sure my alarm is set.

This is a feature that would make me interested in switching to a WinPhone