Preorder Bonuses: Yes, No, Maybe?

It seems like every few days or so there’s another announcement for some kind of preorder incentive. After plunking down a few bucks to reserve a game, players usually end up with some kind of exclusive  in-game content when the game hits shelves later. (Of course, there are exceptions.)

What do you guys think of preorder bonuses? Do they ever sway you into buying something you’re on the fence about? What about bonuses that span several retailers? Do you feel like wherever you decide to shop you're missing out on something important? Or do you find the entire concept of preordering games odious, regardless of what publishers and retailers dangle in your face?

We’d love to hear your thoughts on the subject!