What I really want though is a very simple feature. I don't want my phone to accept phone calls unless the number is in my address book already. Its so straightforward and already implemented in other communication mediums, I do not understand why it is not a feature yet.

Just one vendor including this feature would force all of them to.

My parents do this the old fashioned way. They don't pickup unless they recognize the number.

In fact, my colleagues do the same, and this has actually caused problems for On call if the colleague calling at 4am isn't in the callee's circle of friends.