Someone showed my their new Canon ?5100 dslr and I couldn't believe how small the image was in the viewfinder - having been used to a 1ds2, 5d2 and recently trying the pentax645D.
Last weekend a friend let me play with his new Nex 7. The sun was low and bright, snow on the ground, and I could look at the viewfinder and see the image just fine, with the sun visible off to the left side - utterly amazing, and far better than my own Panasonic GH2. I much prefer the controls on the GH2 (exc. for the fact that I always press the menu when I grip the camera), but the viewfinder on the sony really was excellent.
The image was smooth and seemed to refresh a lot faster than my GH2.
I think the time of the slr with electronic viewfinger, a la the
Sony A series cameras, has arrived, and it is only time before Canon and
Nikon abandon bouncing mirrors.
Whether mirrors will be needed at all (as per the A series for focusing) or will focusing on the sensor become faster as processors get more powerful, I suspect the latter and we will have rapid focus, live view, tilting viewfinders etc..