When Apple stuff is in transit from Apple to the couriers, the tracking just shows the 'Apple Delivery Reference Number' as the 'Carrier Tracking Number', which as everyone's finding, you can't use. However, once the courier allocates a delivery tracking number prior to it being sent out for delivery the Carrier Tracking Number field will be updated to show this.
In other words, if it's showing the same number as the delivery reference, then it wont work as a tracking number. However, if it's a different number (usually beginning 1Z for UPS) then you should be able to track this on the courier's website. Would guess that the proper tracking numbers will start to appear late tonight.
So for all the optimistic people hoping to take delivery today, if your order is still showing the Apple Reference Number then I'm afraid the courier hasn't even processed it yet, never mind despatched it!