I know something like this goes against Sony's or Cannon's business model and their strick guidelines against future proofing cameras.
But for a company like BMD or RED who try to add features to extend the life on their latest cameras (URSA turret) (removable mounts and sensors) it would be a cool Idea to have a slot where one could just replace the processor once it's lagging with a new software features.
I know I would love a BMCC that had the ability to run the new firmware for the URSA and handle the 90fps the sensor is capable of.
As sensors get more and more high end and cheaper it's looking like their life is getting extended because of their quality, but also being replaced because the hardware around them is lacking.
Pretty cool concept for a future BMD camera.