Lonyo, you are suggesting that HL2 isn't "proper" DX9 code? My little old 5900XT certainly does not suck at HL2 in DX9 mode, despite Gabe Newell and ATi's best efforts to ensure GeforceFX would never run DX9 mode in HL2...
No, nVidia didn't write the Doom3 shaders, Carmack did, and he was sensible enough to optimize his code to cater for a wide range of shader power (he wrote partial precision support into Doom3's shader).
ATi needed to rewrite the Doom3 shaders because they were the ones who leaked the Doom3 alpha, and Carmack promised to punish the company responisble for that.
Steelski, 6x AA (an ATi standard AA mode as you point out) is present in HL2, yet there is no option for 8x AA - a standard (present in the driver control panel) AA setting for nVidia cards.
As for your list of games that supposedly run poorly on GeforceFX, I can assure you they don't - I should know - I have the hardware in question to test, and I'll bet you don't.