Because if one reviewer says it, it has to be true.
I'm just having a hard time swallowing that something that is "slower" could be considered the better product. By that measure, the HD 5870 was a "better product" (ran cooler, was quieter, used less power, support for 3/6 monitors on one card, etc.) than the GTX 480, but no one on these forums agreed with me on that. Everybody sang praises of the GTX 480's immense power, and ironically, higher price tag. Then there's the HD 5970, which was quieter and used less power than the GTX 480. The 5970 was easily beating the GTX 480 by 50-70% performance. The 5970 WAS the better product.
Sorry if I sound a bit cynical here, but seriously, you guys need to figure out what your criteria is for "better." It's an nvidia product, so obviously, we're going to like it IF it's a good product. However, @ $700, call me skeptical on weather this is actually worth the money or not.
If the GTX 590 had matched the HD 6990 in performance AND the GTX 590 was the quieter solution, then I would have agreed that the GTX 590 is the superior product. However, as it stands, it's sort of hard for me to believe that the superior product is actually slower AND rings in at the same price as a more powerful video card. I think Nvidia has gotten a little bit too high and mighty this time around.