LG's 27MU67 monitor quietly appeared on the firm's Australian site last month, promising FreeSync goodness from a 4K IPS panel. Today, the display was formally introduced in the U.S. The 27-incher is headed to Amazon, Fry's, Micro Center, and B&H later this month for $599.
According to the official specs, the display uses an 8-bit panel that achieves 10-bit color through dithering. It's calibrated at the factory to cover 99% of the sRGB spectrum, which is fairly typical for a modern IPS unit. Although the specs listed in the press release mention 99% "Adobe sRGB" coverage (likely a reference to the wider Adobe RGB gamut), the product page and PR text only provide the sRGB figure.
The range of available refresh rates spans 40-60Hz, a fairly limited swath compared to some other variable refresh displays on the market. You'll need a heck of a lot of GPU power to push frame rates over 60 FPS at the native resolution, though.
DisplayPort is required for FreeSync, and the monitor serves up both full-sized and mini flavors. You also get dual HDMI inputs, at least one of which adheres to version 2.0 of the spec. LG includes a bunch of split-screen options for the multiple inputs, and it offers a gaming mode with a claimed input lag of only 9.7 milliseconds.