Just checked with a number of Best VBuy in New York area.
Brooklyn, Bay Parkway store
In Person - Guy in Apple shirt, with clipped on Nano - "We will sell it at 10am, when store opens"
44th street and 5th ave
Over the phone - "We will start selling at 5pm"
NOHO store
Over the phone - "Starting sale at 5pm"
Gateway mall (smaller store)
In person, with store manager - "We cannot sell it before 5pm. To start early, it would be a violation of our reseller agreement with Apple. We are getting a Demo model on 10th, which we are allowed to put on display"
So, yes, I would be surprised if ANY store sells it before 5. I kind of have to buy it in Best Buy. Have my Reward Zone certificates, plus Silver status. Also, suggest that you pay for it with Amex, if you have one. Their extended warranty should cover it.