Let me put it this way: I
EXPECT the X1900XT(X) to pwn the daylights out of the 7800GTX 512 in shader-intensive stuff. I mean come on, with 48 shader pipes, that'd be sad if it didn't. But the performance advantage in FEAR extends all the way down to the X800 family. At some points,
an X850XT PE performs the same as a 7800GT! I don't care who you are, that's not right.
And yes, I do say the real competitor to the X1900 series is the 7900 series. Not only is the time of release a factor, as you said, but that the 7800GTX 512 was the only card that had the same amount of RAM coming from NVIDIA, or the closest in price at release (don't forget, at that time the GTX 256MB was over $100 cheaper than the X1800XT). Could NVIDIA help it that the 7800GTX 512 was powerful enough to nearly compare to a future card whose performance they had no way of anticipating?