2012 BMW M6

2012 BMW M6

2012 BMW M6

2012 BMW M6

2012 BMW M6

2012 BMW M6

2012 BMW M6 has been captured in testing by our spy photographers, for the first time testing on the Nurburgring. And it may be packing up to 600 horsepower from a tuned-up version of the twin-turbo 4.4-liter V-8 found under the hoods of the X5 M and X6 M.

Previous reports have indicated the M6 could be replaced altogether by a new super-sports car aimed at the Audi R8, but from the looks of these spy shots, we'll have at least one more round of the M6. With power nearing the 600 horsepower mark, however, it may well fill the rumored super-sports role without a name change.

We've already seen the next-gen 6-Series Coupe and Cabrio in numerous spy shots, but the M6 packs some slight yet significant changes. In the photos, we can see quad exhaust outlets, reworked front and rear ends to snag more airflow while minimizing lift, and a similar but sleeker overall profile compared to the current model. The oddball boat-tail rear-end of the current 6-Series also looks to be much improved on the spied car, though we'll have to see it without the camo cladding to be sure.

The 2012 BMW 6-Series is expected to make its debut at this September's 2010 Paris Auto Show, with the M6 likely coming shortly after. Sales should start sometime next summer. Stay tuned for more details and images as development continues.