As of July 12, Gamestop still had Xbox One bundles in stock and open to pre-order, but these retailer stockpiles are dwindling fast. Amazon is out of Day One editions, but the Standard edition is still up for pre-order. Xbox One Day One pre-orders will hit Best Buy "soon," while Wal Mart pre-orders are still live. Wal Mart, Amazon and Best Buy both have the PS4 available for pre-order, though the launch-day bundles are MIA.
We've contacted Gamestop for clarification on Xbox One availability.