What it may come down to, for those of us who enjoyed the 120 formats, is that there was something rather good about seeing a big image in the viewfinder.
The perfect solution, of course, would have been the ability simply to exchange a film back for a digi one of the same size.
Yes, I get the cost and difficulty factors, but that doesn't alter the concept itself.
Maybe future small cameras will incorporate enlarged LV within the viewfinder instead of on a rear screen; then, we would perhaps have the benefit of a larger, magnified screen on which to compose... Sure, a different shape for cameras, but they have been changing shape since the first one. I think of something built like a 500 'blad, similar size of screen, but the actual sensor any size (probably smaller) you desire it to be. As long as the viewfinder shows you a large image you should be okay, regardless of sensor shape. It should also let you rotate the image (as in PS) if not actually the sensor itself. Christmas if just around the corner...
;-)
Rob