Apple Insider is reporting that some US-based Apple Stores are, following a similar to move by AT&T, starting to sell unsubsidized and off-contract iPhones. Pricing is $599 for the 8GB model and $699 for the 16GB, but in this case there seems to be no restriction on the quantities purchased.
While Apple Insider suggests these units could be unlocked, we're not aware of any official policy or method in place to do so -- unless they're referring to Jailbreaking and running the yellowsn0w software.
Speculation as to why Apple and AT&T are now more fully embracing the off-contract model, of course, centers around their desire to clear inventory prior to an anticipated (by the Internet) hardware revision sometime this summer, perhaps introduced at WWDC in June as the iPhone 3G was last year.
Anyone rushing out to get their off-contract iPhone 3G while supplies last?