Looks pretty official to us.

Like watching Magneto and Professor X make friends in X-Men: First Class, it's still strange seeing old rivals Mario and Sonic be all chummy in Mario and Sonic at the London 2012 Olympic Games, though it's nothing compared to seeing Metal Sonic wielding a tennis racquet.

The 3DS instalment is due early next year, with the Wii release going for sales gold this Christmas.