Android 4.3 has a hidden feature! It's called "App Ops" and it lets you selectively disable some permissions for your apps. Is some misbehaving app constantly pinging your location and draining your battery in a few hours? You can fix that now.

Update! Optional permissions at install

I'm working on my full 4.3 teardown, but I just ran across this and had to add it here:

<string name="grant_confirm_question">Do you want to grant the following permissions?