Reading these forums and over on reddit, it seems a pretty consistent issue that anyone (including myself) who received a UPS tracking number on Dec 3rd does not yet have any details from UPS even though Apple is showing delivery for next Tues, Dec 14th.
I'd seen someone suggest that all the numbers were printed in China, that our MBPs (usually 16"/32gb/2tb) were wrapped on a pallet, and put directly on a UPS plane to the US. The first time that UPS will actually scan them is when they're cleared and handed off to US operations. At least that's an explanation that makes sense rather than all of our laptops have been lost somewhere. It's a substantial group of people, extrapolating from the comments.
I'm also betting that we'll see deliveries starting around the end of the week rather than next week based on the UPS times I've seen between the tracking number being issued and the actual delivery. Apple seems to generally have a slightly later expected delivery date for *most* people.