The new ATI 3800 series cards are coming in mid-November (possibly the 15th if their schedule holds true this time). It has yet to be seen whether or not they will match or exceed the performance of the new 8800GTs.
One thing I can tell you is that I have an 8600GTS in one machine currently and an x1950XT in another (also tried an 8800GTS for a while) and the GTS, which by many acounts should have better quality video playback, is not as nice as the ATI card. I have consistently seen this over the last 7 years or more with the ATI vs nVidia starting with cards as early as the Radeon 8500 series. As much as people would like you to believe that nVidia has caught up to or even surpassed ATI in overall image quality, I would seriously beg to differ. I have displays ranging from my home theater DLP front projector to CRT to various LCDs and, bar none, the ATI cards are consistently better overall in quality of text, videos and gaming image quality--almost entirely independent of the driver versions used or calibration performed on card/software or display device. The nVidia cards may win certain benchmarks or score higher at one time or another in these newer video tests, but I don't see it and I have 20/10 vision and am a self confessed videophile. I will state that nVida has really come a long way, however, because they really used to suck to the point of being nearly unusable in my opinion. I can actually tolerate my 8600GTS (as well as my previous 7800GT with Purevideo for movies) for video and LCD text. I could never say that about previous cards from them that I've owned. The ATI 1900s were just better in every way though. The one thing nVidia had over ATI was their ability to compensate for overscan on certain displays.
I'm waiting for the next ATIs to come out before upgrading to a faster DX10 capable card to replace my current 8600GTS. I hope ATI can catch up with nVidia in the speed, power consumption and heat generation arenas where they truly lag behind current generation nVida cards in the mid to high end ranges.