Sprint still hasn't announced the off-contract price of the HTC EVO 3D but based on the accuracy of the Radio Shack ad leaked to G&E last month, it seemed reasonable to assume that it would be $499.99. It was even more likely when AmazonWireless corroborated the price (knocking off $30 in the process), but lately most of the retailers that will be selling the phone are listing the phone-only price at $599.99.
Wirefly has been doing this since the day the $199.99 subsidized price became official, but the others didn't follow suit until recently. Now both Radio Shack and Best Buy are advertising $599.99 off-contract prices too. Walmart is the only one still sticking to the originally leaked $499.99.
Whether Amazon will end up increasing its price remains to be seen, but at the moment, that's where to go to save $130 on a contract-free EVO 3D.