Retina Display for the Desktop
A recent Daring Fireball post brought the possibility of having desktop monitors with Retina Display pixel density. The original author makes his point looking at new OSX Lion APIs. Gruber goes on to say this is why next iPad will not have a retina display until Apple manages to push that many pixels in a 9" screen. Talking about desktop monitors, I would expect John to dig deeper into the issue, since having printed-like dpi on the desktop is a long awaited dream. I hope he will write more about this later.
Having such amazing resolutions in a cinema display is certainly possible with current technology. Some years ago we probably had doubts about video memory and display bandwidth. There were certainly very-high-density displays, mainly developed by IBM, but not for the average customer. Those monitors were driven by using two high-end display cards simultaneously, each driving a half of the screen real state.
Current high-end display cards can have a healthy 1Gb of video memory, enough for several mega-pixel display, even using acceleration. :-) If this is not enough to do OpenGL over 5120x2880, the display board could just use a lower working resolution. The main problem here I think is the high bandwidth required to get all those pixels to the screen. Perhaps this is one of the reasons why Apple is implementing Thunderbolt within the Mini-DisplayPort.
The problem, however, is not technical, those screens will not have a low price tag.