This is all really great, but my ISP and router situation is not at 100% uptime and about once a week I need to reset them both. I wouldn't be able to rely on this completely :/
"If you use an iPhone 4S or iPhone 5, you can enable Lockitron to sense when you walk up to the door and unlock for you using Bluetooth 4.0. We call it Sense."
From their FAQ: If you have an iPhone 4S or iPhone 5, Lockitron will work even if the internet or power go out. And of course, you can always use your original key
I guesss it also uses Bluetooth for manual unlock and not only for Sense.