Fake...
Looks pretty fake to me. And the weird screenshot size is another clue. http://www.internettablettalk.com/ has more info on the next gen and is probably much more correct.
A screenshot has popped up online that’s claimed to detail part of an upcoming Nokia operating system for internet tablets. Nokia_OS Apparently this UI could feature on a Nokia tablet next year Called “Maemo Harmattan”, the image reveals a vertically scrollable display of the OS’ “Organizer” menu and – according to a …
18 months from now? Nokia's habit of detailing their latest phones 6 months before availability is frustrating enough. Hands up everyone who's excited about products they might be able to buy a year and a half from now.
If Nokia doesn't hit a home run with their Ovi store (and soon) they'll likely be relegated to a low-end phone maker by then anyway.