(Above: The AF Phase Detection Pixels; Image Source: Fujifilm)
By Fujifilm! See:-
http://www.fujifilm.com/products/digital_cameras/f/finepix_f300exr/features/
Well, if this can be applied to larger sensors/imagers like that used in the IDLCs and above later on (currently the above new technology is used in a DC only), then DSLRs will no need to have all those split-mirrors and prisms as well as sensors in a separate AF detection module. As such, there will be no more mis-alignment issues that cause the AF errors. LiveView mode will be much better to use as there will be faster and more accurate AF. And continuous tracking and predictive AF will also be made possible. What a better world it will be!
Thanks, Fuji, for bring us that ground-breaking technology that I think will open up a new era of new echnology that will come! (Thumb Up!)
Update: There is more technical information on how putting additional "AF" pixels on sensors could do the phase detection and job. Here is an explanation on the Sony patent and design (Yes, it's a Sony, not Fuji. Btw, I don't know if Fuji works in the same or a similar way, but I guess that it should be):-
http://olddo.com/bbs/viewthread.php?tid=13800
(Text in Traditional Chinese, for Google translated English page, click here)
So, I think without micro-prisms for the light splitting, focusing accuracy and low-light sensitivity would be affected. Moreover, diffraction would be a real problem by that design (see this diagram). Let's see what the technology will become and how it would evolve! Maybe later on they put micro-prisms on sensors, just like what the sensor makers did that years ago by adding micro lenses on sensors. Whilst theoretically all these are possible, but then it just boils down to the manufacturing cost and money/marketing concerns again..