CMOSIS, the sensor supplier for the new Leica M, could also be the sensor manufacturer for the just announced Blackmagic 4k camera according to EOSHD:
"Their Super 35mm 4K sensor is the “CMOSIS CMV 12000″ and the specification is a close to the Blackmagic Production Camera. Also the pin layout as shown above looks identical despite the low resolution shot of the sensor in Blackmagic’s promotional material."
FYI - CMOSIS also has a 70MP full frame sensor in their current lineup:
