Presented in the first xf86-video-ati 6.9.1 release candidate (v184.108.40.206) are several new features. Mode-setting support for the RV710 and RV730 GPUs has been added with DCE 3.2 support to the DDX driver, initial support for Apple eMac computers, improved HDMI support, enhanced TexturedVideo / X-Video support, interlaced mode support, EXA fixes, big-endian AtomBIOS support, and R500-700 TV-Out support.
In the realm of TexturedVideo improvements are bi-cubic shaders, large triangle rendering to decrease tearing (Radeon Driver Gets Tear-Free X-Video), and v-synced X-Video support.
The R500-700 TV-Out support that's made possible through the use of AtomBIOS isn't enabled by default but can be toggled through the xorg.conf ATOMTvOut boolean option.
The xf86-video-ati 6.9.1 release candidate is also made up of quite a few other changes too. The release announcement with full change-log and source download links can be read here.