I agree, the last remnant is stupid. Everyone with an ATI card knows they probably can't play it. Funny, considering it was developed for a console with an ATI chip.
Let's do some simple math here to prove if ATI really has the price to performance advantage.
I'll use far cry 2 because I think it's a very fair description of DirectX10 power, "WIMTBP" be damned.
Top range, GTX 295 vs 4870X2, there's a performance difference on par with their respective prices, especially in the highest res and AA/AF setting.
Higher-mid, 4890 vs GTX 275. Again, the performance percentage is very close to the twenty dollar difference between cards, and exceeded in nvidia's side at the highest res.
High-mid, 4870 vs GTX 260 216, even on Left 4 Dead, a source engine game favoring ati, the 260 comes out on par. This is a tie, really. But don't kid yourself into thinking the 4850 is any kind of match for the 260.
Mid-range, 4850 vs...well, if you take a GTS 250, they're very evenly matched. If you REALLY want a 9800GT for the same price, well, sucks to have an IQ of 50.
Also factor in the growing use of Physx and ATI doesn't make a very compelling argument. Prices are matched frustratingly well and the only real "killer deal" is a 4850x2 for slightly over $200.
Know that I like ATI and I'm not saying they're bad cards, I'm just saying they're only on par with Nvidia's offerings, not above them.
Just remember that DirectX11 will be in full swing in around six months and none of this will matter anyway.