The Verge got to try it out, and the tech site said that "it's good, it's very good." They played existing games including Asphalt 8: Airborne and Injustice: Gods Among Us and seemed impressed. Since the games' textures and graphics were designed for lower resolutions, "they don't look as awesome as they could, but the sheer fact that they can be run at 4K with a perfectly playable frame rate is impressive," the site said.
The Qualcomm tablet on display at the tech show appears to be merely for demonstration purposes, though. Qualcomm announced the new Snapdragon chip last November, but it's not due to show up in any retail devices this summer. When it does, though, 4K resolution tablet gaming may well become the new standard.
There's debate as to whether jamming so many pixels onto the relatively small screens of tablets and smartphones will actually provide much benefit to the human eye, but that seems to be the direction the industry is headed regardless.