Several of the Mac rumor sites have been hinting at the next generation of Macs having extremely high resolution displays ranging from 2880x1440 in a 15" laptop all the way up to an amazing 5120x2880 on a 27" desktop monitor (although that last number is SO high that the rumor sites are questioning it themselves). The major purpose of these resolutions is for Apple's "Retina" pixel doubling, where they use four times as many pixels per character (2x in each direction) to provide ultra-sharp text and graphics. I have a Retina iPad, and it really IS incredibly sharp.
Another use of the doubled resolution, however, is to provide a lot of detail on photographs... The Retina iPad is a very good photographic display device, because it has very close to the detail of a print (it's small, but it is highly detailed). With good source material, it's approaching the look of a large-format transparency on a light box. Its color gamut is also pretty good (above sRGB, although not up to Adobe RGB). If the proposed Mac Retina displays had good gamut, and were relatively easy to calibrate, I could see them being very good image monitors (even a (horizontal) D800 image could be displayed at 50% on that 27", and 12 mpix DSLR images would come close to fitting at 100% - 180 pixels at the top or bottom would be scrolled, plus a bit for the menu bar, assuming palettes on the sides). What do other folks think about the utility of extremely high resolution image displays... I'd love a 27" Retina iMac with a cheap second monitor for palettes, and that primary display for the image (assuming that the monitor was otherwise suitable - I'd even put up with glossy if it had resolution and gamut).
-Dan
