Update #3: From iLounge:
"Although iLounge contacted Walmart before posting this story to confirm that the $399 pricing did, in fact, apply to the fourth-generation iPad - and received unambiguous written confirmation of that detail from a spokesperson - the company has now retracted the claim, suggesting that the $399 price applies solely to the third-generation iPad."
However, we have received emails claiming some Walmarts are not even honoring the sale price for the iPad 3.
Update #2: There seems to be some confusion as to what iPad is on sale. According to a Walmart rep, the deal is "the iPad 3 at the iPad 2 price". User comments on iLounge also say the deal is for the iPad 3.
"I just called my local Walmart and they said the $399 pricing is for the 16GB iPad 3rd generation, not the Retina display."
Update: Quick correction. Walmart is reducing the price of the iPad 3, not the fourth-generation iPad like we originally stated.