To those that are curious about them, I have installed them for my parents. They do work quite well. The video and audio are quite clear (even at night). Setting them up is simple, and the web UI is simple enough that my parents do actually look at it.
You can build a better camera with a Raspberry Pi 2 for less that does not "phone home" to it's manufacturer.
I don't leave it on all the time, but I use it occasionally on a whim:
1. Started a 3d print, then went out to dinner, checking on the progress from my phone. Not required, but I was curious.
2. Put it in the corner of the game room and recorded an epic foosball match. I then grabbed the footage using the online timeline view and uploaded the clip to YouTube. Frivolous, but fun.
3. Checked in on my cats during my vacation. I know...
4. Timelapse of moving into a new office.