According to the release notes on AMD's support page, the  Radeon Software Crimson Edition 16.8.1 drivers bring support for the newest Polaris GPU-based graphics cards, the Radeon RX 470 and Radeon RX 460, as well as bring a single new Crossfire profile for F1 2016 game and a couple of fixes. 

The list of fixed problems is not long but it includes some rather important fixes like the fix for Radeon WattMan software and problems with the maximum memory overclock on the Radeon RX 480 graphics, fix for Firefox browser when the hardware acceleration is enabled, and some various fixes with Crossfire in games like Overwatch, The Division, DOTA 2 and more. 

Working on all graphics cards since the HD 7700 and HD 7900 day, the new Radeon Software Crimson Edition 16.8.1 drivers are available for Windows 10, Windows 8.1 and Windows 7 OS in both 32-bit and 64-bit flavors.

As always, you can check out the release notes as well as find all the full release notes over at AMD's support page.