When we mention 4K monitors, they typically have a resolution of 3840×2160. Digital Cinema 4K adds an extra 256 pixels horizontally, yielding 4096×2160 (an aspect ratio between 17:9 and 19:10). LG Electronics has just released a monitor at this resolution for video and graphics professionals, and its feature set is strongly focused on that market.
First, with a Digital Cinema 4K resolution, the monitor is capable of previewing content in that resolution without scaling or cropping. Alternatively, software could preview consumer 4K ("UltraHD") and have a little leftover room for user interface elements.
What really sets this apart from other monitors is its color space features. This is an actual IPS panel, providing wide viewing angles, and it supports 10-bit color input for smoother gradients. Its color space is large, too. Beyond sRGB, it also covers 99.5% of the AdobeRGB color space and 97% of the DCI-P3 gamut. LG even has a mode that splits the monitor into two, one side in AdobeRGB and the other in sRGB. This is intended for artists and publishers to see content both in the color space of professional printers (AdobeRGB) and websites on consumer displays (sRGB).
While I believe this panel is rated at 60 Hz, it does not explicitly say that anywhere (that I found). I emailed LG for clarification and I will update if/when they reply. Update (Nov 4 @ 7:45pm EST): Still no word from LG, but one reader pointed me to an Overclockers UK product page that claims 60 Hz over DisplayPort and Mini DisplayPort. A second reader claims to own one of these monitors, which is running at 60Hz over Mini DisplayPort. It sounds like it supports 60Hz SST.
If it is a 60 Hz panel, this is an interesting, 31-inch display, especially at an MSRP of $1399.99. It undercuts competitors, like the Dell Ultrasharp 32, by over a thousand dollars. The LG 31MU97 is available now at a few online retailers.