I know it's a matter of aesthetics, but I prefer the iPhone with the black faceplace (speaking as a guy with a white 3GS). The photo looks legit, so we're not doubting it, though the home button looks seriously recessed. Perhaps there's a case or layer of plastic on top of it, or maybe a shadow is playing tricks.
In any case, it looks like there will be an all-white iPhone 4G. So there you go.
Update: As of this writing, tw.apple.pro is down. We'll let you know if it returns.