I really like the idea of setting a time frame to silence incoming calls, email and other alerts. I would sometimes forget to turn the silence switch on when I wake and miss calls...so having the phone automatically go silent and then turn back on in the morning is a great feature for me. The only problem is that it does not completely silence the phone as email still "dings". I am sure that Apple's development team has a reason...but I think that Do Not Disturb should apply to all incoming communcations. I really like the iPhone and could not live without it, but I sometimes find that certain features are not quite refined.