The reviews are out and the word on the street is that AMD's HD 6990 is indeed the fastest single card available right now, however it does cost $700. I recommend reading the last page of [H]ard|OCP's review because they have described the performance and the value of the HD 6990 when it is compared to a GTX 580 SLI, GTX 570 SLI and HD 6970 CrossFireX setup.
I'll be spending the rest of the day adding cards and reviews to the site. If enough reviews contain overclocking data, I will try to post an overclocking roundup for y'all.
I have a hunch that this week is going to be very exciting for graphics card enthusiasts. I am pretty confident that Nvidia will be using PAX East to celebrate the arrival of their GTX 590. One thing is for sure, I will be there, and I will do my best to make you all feel like you are there as well.
For now all the HD 6990s look the same except for the sticker that the manufacturer has slapped onto the card. I haven't seen Gigabyte or Asus' card yet, so right now PowerColor has the prettiest sticker and Diamond has the most boring sticker.