The only time I'll pre-order a game is when the game won't get made otherwise (like Kickstarter or Early Access), and I have loads of faith in the developer. Luckily I haven't been burned yet (though I consider Star Citizen a near-run thing until it delivers). Bonus if the game is already in a playable and enjoyable state.

Pre-ordering a AAA game? No thanks. Most pre-order bonuses aren't worthwhile because they can't offer people too much or retail purchasers will get pissed off.