The release of a 5,120x2880-pixel wallpaper image indicates that Apple could bring high-resolution Retina displays to its iMac line of desktop all-in-one computers and external monitors.
The 3.3MB "OSX_hero_2x" image shows the blue and green ocean wave that's featured in the upcoming OS X Mavericks version of Apple's operating system. Its width and height are exactly double that of of the 2,560x1,440-pixel screen on the current 27-inch iMac.
As Apple has spread its Retina displays across iPhones, iPads, and MacBook Pros, it's released double-resolution graphics for user-interface elements such as icons and wallpapers.
The Retina displays have yet to arrive on iMacs, MacBook Airs, or Apple's standalone external monitors, though.
At its Worldwide Developer Conference (WWDC) Monday, Apple announced some hardware details of a new tubular Mac Pro, though not how much it would cost or when exactly it would arrive. The machine can support up to three external monitors with 4K video resolution, and Apple is working on a Final Cut Pro X update also geared for that high resolution.
A Retina-class external monitor would be a good match for that Mac Pro hardware, and video-editing pros are often better able to withstand the sticker shock of what would likely be expensive hardware.
Updated at 4:09 a.m. PT to correct the list of Macs that have Retina displays, which currently is only MacBook Pros.