Design-wise the large wheels and aggressive, ABT-style nose is a strong departure from the relatively understated appearance of previous S8's. Could Audi be so bold? We're not convinced. The other big mystery, of course, is what's underneath the hood. We've heard the RS6 twin-turbo V10 putting down around 600 HP.
UPDATE: It looks like our skepticism was well-founded. This is but a 'chop put together by someone over at World Car Fans. Thanks to porschecarreragtmay6 for digging it up.