I thought they added something in iOS 3 that did encrypt the phone and that's why the erase is so fast now? I also assume that if you put a passcode on with th

I thought they added something in iOS 3 that did encrypt the phone and that's why the erase is so fast now? I also assume that if you put a passcode on with the 'erase after 10 incorrect attempts' setting that this would be permanently erased if they get your passcode wrong 10 times...?