All I can give you on this one is "this is what we know, so far" facts.
You can buy an iPhone off the AT&T web site using a zip code from, it appears, every major city in the United States, except one: New York City.
Try it yourself. I did.
Here's a link to the AT&T's iPhone page. You have to plop in a zip code before closing the deal.
Now! Help yourself to any zip code on the Isle of Manhattan and see what happens.
The Consumerist was the first to break this interesting little glitch over the holiday. AT&T hasn't commented yet on what gives.
Naturally, one has to wonder if this has anything to do with not having enough bandwidth on the NYC metro area 3G network to handle the current level of smartphone traffic (some estimates put dropped call rates as high as 30% in NYC).
It doesn't make sense that iPhones were perhaps just sold out in New York over Christmas. Why couldn't a shopper in New York get the same iPhone shipped from destination wherever, as the shopper in Chicago?
I'll let you know what else I hear on this one.