Today Gamestop leaked the specs for battlefield 3  
They  were removed from the site within 10 minutes of the leak, but internet is the internet.
 
Minimum

Hard Drive Space: 15 GB for disc version or 10 GB for digital version
OS: Windows Vista or Windows 7
Processor: Core 2 Duo @ 2.0GHzRAM2GB
Video Card: DirectX 10 or 11 compatible Nvidia or AMD ATI card

Recommended

Hard Drive Space: 15 GB for disc version or 10 GB for digital version
OS: Windows 7 64-bit
Processor: Quad-core Intel or AMD CPURAM 4GB
Video Card: DirectX 11 Nvidia or AMD ATI card, GeForce GTX 460, Radeon Radeon HD 6850