ATI will soon launch the DirectX 11 performance card, something that they have labeled the RV870 and something that AMD calls Evergreen.
The new card is around 1.6 times faster than the RV770 chip and will rock your socks off as far as speed is concerned.
The big issue is that by late November Nvidia might launch its Geforce GT300 chip, that might end up even faster, but at the same time Nvidia's DirectX 11, 40nm chip will also be bigger and probably hotter as well.