The currently available Black and White versions differ only by the color of the back - the front has a black bezel around the screen in both of them. Apparently, Samsung has been working on a white bezel for the White version as these photos show.
For comparison, here is how the old one looks.
Color of the front aside, the specs of the Tab 10.1 and Tab 7.0 Plus remain unchanged. There's no info on when they'll be available or if there will be a difference in price.
Thanks Tran Quoc Huy for sending this in!
Source (in Vietnamese)
I Love Samsung and I Love White
So Nice samsung
When are the white bezel 10.1 tabs coming to BEST BUY in the USA?