Ah, GPU wars - don't you just love them? NVIDIA have recently released their explosive GeForce GTX 590 dual-GPU video card and stated that it was the "World's Fastest Graphics Card" yet, never proved this with an industry-standard benchmark like 3DMark 11.
AMD have called them out on this and directly asked NVIDIA to "prove it, don't just say it". Dem be fighting words meester. Fisty Cuffs, go! AMD also listed a bunch of review sites pointing to their HD 6990 beating out the GTX 590. Salt, wound, hurt.