If you had no Windows 7 support, you will get no Windows 8 support.
ATI have Windows 8 drivers up and ready for the HD 7000, 600o and 5000.
Conspicuous by their absence are the HD 4000, 3000 and 2000. Windows 8 has basic support for these, so don’t expect good gaming graphics even with the simpler games. For general use, they pass.
nVidia on the other hand are supporting everything from the Geforce N6600 and beyond, Quadro, Tesla and ION.
nVidia 3DVision is not supported along with all legacy products, many of which didn’t get Windows 7 support either.
It looks like I will be out shopping for a video card quite soon. Will you?