Acc. Steam with minimum graphic (and small map?) should be following satisfactory. But to be sure you have to wait for the final release.
In my opinion the requirements are low. (too low?)
OS: Windows XP, Vista, 7 or 8
Processor: Intel Core 2 Duo
Memory: 2 GB RAM
Graphics: Nvidia GeForce 8800 512 MB, ATI Radeon HD 3850 512 MB
Additional Notes: Mouse with wheel