Just keep in mind there are always problems in the beginning.
OK, I can understand that for games that are "new" to the scene and they don't know what to expect, but Activision and Treyarch both knew the amount of preorders as well as what has sold in the past. If you don't think that they can prepare for something like this, you're mistaken. The reason why is because they don't want to spend the money. Period. :'(