They've announced the system requirements too, have posted them in a new thread but my post needs to be approved by a moderator.
So here they are again:
Minimum System Requirements
Operating System: Windows® XP SP3/ Windows® Vista SP2/ Windows® 7
Processor: Dual Core CPU
Memory: 2GB RAM
Hard Disk Space: 8 GB Free
DVD-ROM Drive: Required for disc-based installation
Video: 256 MB ATI HD2600 XT or better, 256 MB nVidia 7900 GS or better, or Core i3 or better integrated graphics
Sound: DirectX 9.0c-compatible sound card
DirectX®: DirectX® version 9.0c
Recommended System Requirements
Operating System: Windows® Vista SP2/ Windows® 7
Processor: 1.8 GHz Quad Core CPU
Memory: 4 GB RAM
Hard Disk Space: 8 GB Free
DVD-ROM Drive: Required for disc-based installation
Video: 512 MB ATI 4800 series or better, 512 MB nVidia 9800 series or better
Sound: DirectX 9.0c-compatible sound card
DirectX®: DirectX® version 11
Other Requirements: Initial installation requires one-time Internet connection for Steam authentication; software installations required (included with the game) include Steam Client, Microsoft Visual C++2008 Runtime Libraries and Microsoft DirectX.
Internet Connection and acceptance of Steam™ Subscriber Agreement required for activation. See
www.steampowered.com/agreement for details
Software license terms available in game manual and at
www.take2games.com/eula. Non-transferable access to special features such as exclusive, unlockable, downloadable or online content, services or functions may require single-use serial code, additional fee and/or online account registration (13+). Access to special features may require internet connection, may not be available to all users, and may, upon 30 days notice, be terminated, modified or offered under different terms.