This happens for every major item and people get in a panic as much as a week before release.
What's funny is when you think about it, it's weird how people will freak out over a preorder which a company will have plenty of time to plan and organize all those shipments well in advance for things to go smoothly, but nobody sweats about placing an order for an in stock item which is unplanned on the businesses end and just one of thousands of orders being fulfilled that day, and worrying if that will ship out or arrive on time.
Logically, the impromptu order should have more risk than the preorder, but people reverse which one they freak out over.