The PC beta of the game will end up supporting not just 4K resolution and uncapped framerates (so why stop at 60?), but also 21:9 monitor support, and a full range of full fledged, adjustable graphics settings.
A PC version of the game will follow in October, a little over a month later.
It will also end up making history by becoming the first non Blizzard game to be supported on Battle.net.
The content of the beta seems to be similar to the beta that was held on consoles a while ago.