That's right, Dell is releasing the Dell UltraSharp 27 Ultra HD 5K Monitor with a resolution of 5120 x 2880 for a mere $2500 just in time for Christmas. That is just under 6.5 million more pixels than 4k which is an impressive jump and should look very interesting on a 27" display!
While we may not have TV content to justify this resolution gamers with extreme GPUs should be able to take advantage of it as soon as it is released. You will probably be able to turn your anti-aliasing settings down with pixels that small. It will also have 16W integrated Harmon Kardon speakers and quite likely a few USB ports. Surround setups are going to need every PCIe lane you can toss at it though, good thing those 295X2's are on sale right now! They've also added some information about their 4K displays here.