Buy.com is offering an official Apple Unlocked iPhones now for $799. This is an official Apple iPhone which isn't jailbroken. You can do iTunes updates and not have to worry about locking your iPhone up again. Apple warranty also applies.
Strangely, they say that the iPhones may be from other countries so they might have instructions in languages besides English.
This looks like another inventory clearing measure by Apple in anticipation of upcoming new iPhone models in June.
If you've wanted a Tmobile iPhone without jailbreaking hassles/issues, now is your chance. Or perhaps you travel a lot and want to be able to change SIM cards as you go? Check the video on Buy.com's website.