Same here, @ apple store San Francisco, I asked for AT&T 32GB black 4S, MC919LL/A and said I wanted to pay full price. They asked if I was an existing iPhone user and I said yes, passed on the AppleCare+ and paid for phone still shrink wrapped.
Dropped tmobile sim into phone, then synched to iTunes to restore from backup. Received tmobile signal, EDGE, I can use SIRI and picture messaging, it was using the settings from my previous phone.
Sweet. No need to wait until November.
Sweet indeed!! I purchased a sprint, however I'm wondering since 4s has both CDMA & GSM, if it's unlocked to use on Verizon or Sprint. If so, maybe I'll cancel my contract and go the prepaid route.