Same old same old. Last I looked the latest generation cards are completely unsupported with the current drivers (par for the course), video overlay bugs with TV out render the 'old' cards (e.g., 9600) completely unsuitable for DVR use, and the working cards have abysmal performance compared to Windows or NV products a notch or two down. There is still no support for mpeg2 (or any other) video decoding with any ATI card.
Stay away from ATI for Linux. You are welcome to read the horror stories on phoronix and rage3d, or just pick up an older card to see just how bad the driver is. ATI drivers are the reason I migrated to Windows.
AMD is somewhat Linux friendly, so that may or may not be changing in the coming years. Only time will tell.