Gotta love (and hate) rumours.
Good lord, how much is that going to cost (if it's true)?
An incremental increase in the size of the sensor is going to increase the price like crazy, no matter how many megapixels there are. 30, 40, 50, 60, 70, it doesn't matter.
On the bright side, the 36x48mm 33 and 39MP backs should decrease in price. Yay...?