Apparently US Chain, K-Mart, has received MW3 and has been advised to put it up for sale immediately.
A Kotaku user has claimed that a K-Mart store in Tampa. Florida sold them a PS3 copy of Modern Warfare 3 ahead of the game’s November 8th release date.
The user also offered a picture of the game.

Now, I must stress that this has not been confirmed and at the moment is a rumour.
For all we know that picture could be a fake. If K-Mart have broken the street date then I’m sure Activison will not be happy.
Source: Gamepur
UKZ-N3M1515
Happens all the time with indie stores. One local to me sells every big game a few days early for £60 or so. Halo reach, Mw2, Blops, and now BF3 are ones i know about. You’d be surprised at how many people pay these prices to have it a few days early.