Just hours ahead of the kickoff of WWDC 2011, Wal-Mart representatives have sent an email announcing a sale on the iPhone 4 until the end of June. The $50 price reduction brings the cost of a new iPhone 4 to $147 with a two year contract with either AT&T or Verizon. It is unclear whether the sale is merely intended to stimulate demand for the iPhone 4 or an indication that the iPhone 5 launch is near.