Well the 9800gx2 is two cards clued together, and the 280 is single core, so it is definitely usefull in highend machines. I am guite sure that two 280's in sli is much better than two 9800gx2 in quad sli.
It's not a cheap card but it's the best you can get if you have a lot of money! The only thing that can be bad, is that 4870 X2 scales really well when using two of them at the same machine, but if you want to have the fastest thing in the earth at any cost possible, this is your best choise.
I am not personally ready to put this much money to GPU. But I did'n buy 8800 GTX either. Most propably I will take ATI:s new 4000 series card next, because I have somewhat limited budget. All I want to say is that this card is not so bad as many has said in these comments. It is most definitely the fastest single GPU solution you can get!
The temperatures were guite low, the power comsumption were not so bad, when considerin how big the chip is! There definetily was somethig wrong with the cooler, it was not slowing down the speed, so it's something that can be easily remedied.
This is not a "budget" card. Those will come later. And the article was actually good. It's points out that Nvidia has remedied the weak parts of it's previous generation. If you want to have a card that can run your 30 inch monitor, this is your best choice! The results at high resolution were guite impressive considering that the drivers are not so good at this moment. One two month later we can see better results in far more wide rage of games. Now it was easy to see that only few games were optimised for 280.