I think their 3dmark06 scores are kind of low. I have basically the same setup as they do, but with a dual core instead of quad, and DDR2 memory instead of DDR3... and i get almost 11k with 3dmark06 and a stock eVGA 8800GT 600/900.
In addition, I know the 8800GT is a smoker...my brother just picked up an EVGA Superclocked. However, I wouldn't call out all the stops based upon tweaktown's review...we have to keep in mind that this isn't an official card, and neither are the drivers.
Also, I didn't read the article too thoroughly, but it seems that all the tests were done without filtering turned on. On the last page, they flip on filtering and the GTS pulls ahead by a good margin. I dunno about you guys, but enabled filtering is one of the main reasons I buy a card.
I'm looking to buy as soon as the Q9450 is released. Whatever is out (and obtainable) by that time is what I'm going to get. The 512 GT is a very nice card, and I'd be happy with one of those, all things considered. However, if a 1 gig GTS is out by then, I'd be strongly tempted. We'll see....