wow, so with my 5850 I can expect a MINIMUM of 40 fps playing a game with tessalation improved lighting and filtering effects - and that's with AA!!. That's pretty awesome in my opinion. I worry more about the fact that 3gb of ram is reccomended where as I am still using my XP elitist set up with 2gb. It isn't something that has occured to me before as marketing benchmarks tend to focus on the GPU and CPU performance in games, nor is it something I have ever noticed as a "reccomended" amount in the specs. Fun times ahead.
Since you're running XP, its all a huge moot point since you're stuck with DX9. DX10 and 11 have, and will always be only for Vista, Win7 and future Windows OSs. So you're going to need a new OS to take advantage of the tessalation and lighting and all that.