You know. That's something that kind of bugged me while I was watching the keynote again the other night.
Do you have to turn the phone off when not in use? If so, when you turn it on, do you also have to unlock it? Why two layers of "security"? Will it turn on that easily in your pocket?
If it's off, will it still let you know when you get a call or SMS? If not, then how will the screen act while it's locked? Will it go dark after a few seconds until you touch it? What if it's in your pocket? Will it remain off thanks to the proximity sensor or will it keep turning on and off?