Whatever. Quad SLI needs to mature, it still suffers driver problems. Becides, you still need a SLI motherboard to use just one 7950 GX2 because both GPU's are still in SLI mode. Also, nVIDIA is only doing one 7950 GX2 at launch, then allowing Quad SLI later.
I would rather wait for ATI's R600 core.
It'll be the fastest DirectX 9 card in the world and it'll have support for DirectX 10. With 64 Unified Shader Processors and 16 texture units, it'll be a force to be reckoned with. Keep in mind that these are unified shader processors, not the traditional independent shaders. It's basically the Xbox 360's Xenos GPU but on steroids. It's guaranteed to have over 650mhz in core clock speed and it'll implement high-speed GDDR4.
Now that's an nVIDIA anything killer in one package. Imagine if you CrossFire two of those beasts.