BimmerBoost provided a rendering of the F12 M6 in April and stated that it would only make sense for an M6 to follow considering development already went into the next gen M5 powertrain. It would be logical for the M6 to share it just as BMW did with the previous generation M5/M6: http://www.bimmerboost.com/showthrea...6392#post16392
Autoblog has provided of spy photors of the fixed roof F12 M6:







Our rendering of what the finished product may look like:

Expect the M6 to share the M5's powertrain, which means a twin turbo V8 with around 580 horsepower and a DCT.





