The latest AMD Catalyst fglrx 13.30 RC3 driver is now available to all Linux users. The only changes officially mentioned by this first fglrx 13.30 series driver release is support for the AMD A10-7850K with Radeon R7 graphics and the AMD A10-770K APU with Radeon R5 graphics. Expect a 13.35 series driver release soon with crypto-currency mining improvements and other enhancements while further stabilizing their first-cut AMD Kaveri APU graphics support.
Sans the open-source driver, AMD Kaveri APUs on Linux are in decent shape and the first Phoronix benchmarks to be shared are just minutes away.
The new AMD Catalyst Linux Beta driver can be found from this web-page.