In some new titles when detail levels are set to high, the 9800XT with it's clock speeds and 256MB ram, can vastly outperform the 128MB 9800 pro. But most the of the time they are pretty close. For an extra $30 the 9800XT would be a great choice. Problem with the 9800XT is that it still costs $300 and 9800 pro's are under $200. At $300, it approaches the price of the X800 Pro, which can be found in the $330-$350 range. The X800 pro is much quicker, so again the 9800XT loses. And the GF6800GT usually outperforms the X800 Pro and starts around $350.
Anyway, the 9800XT was the king once, but unless the price drops alot before supply dry's up, the 9800XT will never be a smart buy.
ABIT IS7, P4 2.6C, 1GB Corsair XMS 4000 Pro Series, Radeon 9800 Pro, Santa Cruz, TruePower 430watt