I bought mine a few weeks ago while they were still not in stock at that AT&T Store, but I only had to wait three days for it to come in (The estimate at that time was a 7 day wait). When I went back with my brother-in-law to get his a couple weeks later, they had plenty in stock. Apparently, the shipment that brought my iPhone was the first of many shipments that stocked this store.
Interestingly, when I got my iPhone, there were two working models on display. When we went back, the display was still there, but the working models were gone (though the docks and tethers were still there). When I went back recently, I saw the same thing.
MotionMan