High-definition TV is so last decade. Now there's "ultra high-definition," or UHD TV. So what's the difference? A 4K UHD TV supports a 3,840-x-2,160 display resolution, which is 4 times the resolution of regular HD, and an 8K model supports a 7,680-x-4,320 resolution, which is 8 times what regular HD offers. And, part of Samsung's CES blitz is reportedly a 110-inch UHD TV (the previous rumor was an 85-inch UHD TV, but the stakes have apparently been raised).