Everyone's said it already, but preordering basically guarantees you will get one and you get free stuff with it. Preordering almost has the same mindset as going at midnight in that you want to make sure you can get it without the chance of it selling out. I'd personally take the free gifties over having it at midnight anyways, simply go pick up the game when you wake up and it will feel no different
plus you won't get tired and want to sleep if you start playing in the middle of the night.