Apparently numerous Targets across the US have been putting Killzone 3 on the shelves early, with one report of employees specifically saying they were given permission to sell the game early. There's been multiple accounts of this posted on gaf so far, from various people across the country:
http://www.neogaf.com/forum/showpost.php?p=26021834&postcount=1042
http://www.neogaf.com/forum/showpost.php?p=26006142&postcount=882
http://www.neogaf.com/forum/showpost.php?p=26000389&postcount=830
http://www.neogaf.com/forum/showpost.php?p=25984522&postcount=697
Including a picture: