Jeez. 4K displays are coming down in price like crazy lately. One of the latest introductions, Samsung's U28D590D, is now available through the Newegg marketplace for just $799.99. Yes, that's technically $100 over Samsung's MSRP, but it's still peanuts for a 28" monitor with a 3840x2160 panel. Amazon also has the monitor listed for $698.99, but it's not yet in stock. According to AMD's Robert Hallock, this new monitor supports 4K resolutions via DisplayPort at 60Hz using single-stream transport.
Thanks to single-stream transport, this monitor should be detected as a single panel when hooked up via DisplayPort. That may not sound like much, but it's a rarity in the 4K world, where the limitations older scaler ASICs cause many displays to work as two separate tiles. This tiling arrangement leads to the same kind of awkwardness you'd get out of a dual-monitor setup, and it's far from ideal in games. (Scott outlined these hurdles in detail here.) The Samsung U28D590D should be hurdle-exempt. According to Hallock, AMD "worked very closely [with] the scaler vendor" on this display.
What else? Well, the U28D590D has a TN panel with 170°/160° viewing angles, which are narrower than what you get out of the finest IPS panels. But the thing also has LED backlighting, 370 cd/m² brightness, a 1000:1 contrast ratio, a one-millisecond gray-to-gray response time, and support for "one billion colors," which is presumably shorthand for 10-bit color support. We've had a chance to look at some other 4K monitors with TN panels recently, and they look surprisingly good—good enough to make us overcome our usual IPS snobbery.
I'm glad to see 4K displays stray so far from their pricey beginnings. I also hope this surge of affordable 4K displays (and 4K laptops) will motivate developers to implement better high-PPI support in Windows apps. I wrote about the dearth of high-PPI apps and Windows' somewhat awkward coping mechanism five months ago, and we're still not there yet.