Nvidia's Power Of Three

Nvidia's answer to AMD's latest platform offers.

Being left devoid of a good partnership since the acquisition of ATI by AMD, Nvidia has took the only other route possible, giving in to Intel's current stance on chipset licenses.
Like what happenned with the X58 chipsets and the Core i7 900 platform, Nvidia has agreed to provide SLI support on Intel based chipsets for LGA 1156 processors. That comes at a cost though:

The license terms are thankfully a lot more palatable than they were with the initial X58 launch. To support SLI a motherboard manufacturer simply has to pay NVIDIA $30,000 up front plus $3 per SLI enabled motherboard sold. In turn NVIDIA gives the motherboard manufacturer a key to put in its BIOS that tells the NVIDIA display drivers that it’s ok to enable SLI on that platform.

The choice of platform can now be LGA 1156 CPU + P55 motherboard + two/three Nvidia GPUs. The new LGA 1156 LGA CPUs have 16 PCI-e lanes on CPU, providing SLI support in x8/x8 mode. This leaves not much choice from Nvidia other than license SLI support, which is also a sign that new Nvidia chipsets may take a good while to arrive, if ever. Nvidia currently has no license to manufacture chipsets for either QPI interconnect, used with LGA 1366 CPUs, nor the DMI bus used to connect LGA 1156 CPUs to the P55 PCH.
Nvidia's CEO has promised new chipsets soon but the ability of Nvidia to sell chipsets on the new architectures is still doubtful.
Intel seems to be keen on closing Nvidia out of it's platforms, as it will release it's own graphics card, codenamed "Larrabee", in a near future.