Northlight Images has uncovered a patent showing some curved sensor technology. The interesting part of this patent, is that the level of curvature in the sensor changes depending on the focal length.
You can see in the image above that there is a piston like device that will change the curve of the sensor.
As pointed out by Northlight, a “flat” setting is included here as well, so there should be no compatibility issues with old or third party lenses.