Minimum:
Dual core CPU (any Core 2 Duo or better will do)
DirectX 9, Shader Model 3 compliant graphics cards (GeForce 8800, GeForce GT220 and above)
2GB RAM
20GB Free Disk Space
Recommended:
Windows Vista/7
Any Quad Core CPU
DirectX 10 compliant graphics card (GeForce GTX 260 and above)
4GB RAM
20GB Free Disk Space
Optimum:
Windows 7
Core i7 CPU
NVIDIA DirectX 11 compliant graphics card (GeForce GTX 480 and 470)
6GB+ Ram (Hoping the engine will be smart enough to utilize over 4GB of RAM)
40GB Free Disk Space
Enabling 3D Vision
NVIDIA GeForce GTX 275 and above recommended
A 120Hz (or above) monitor
NVIDIA 3D Vision kit
Microsoft Windows Vista or Windows 7