Oh No! SLI is back.
Tom's Hardware and others are reporting that NVIDIA is releasing their newest 6800 series graphics cards with the ability to plug two of them into PCIx16 motherboards to essentially double the video throughput. It also essentially doubles the price of the system. Not to mention that the required motherboards aren't widely available. Still, if you feel the need for speed, and have no limit on your credit card, this should interest you.