During Episode 28 of Kojima Station, the staff talked a bit about the upcoming PC version of Metal Gear Solid V: Ground Zeroes. They showed screenshot comparisons (comparing the PC version with the PlayStation 4 version) on which you can see some of the additions, such as the enhanced number of light sources. The shots below are stills taken from the show.
Also, these are the settings you can play around with: Windowed mode, resolution, display, v-sync, frame rate, model detail, textures, texture filtering, shadows, lighting, screen filtering, effects.
The PC version will be released on Steam December 18th.
Update: Two direct feed screens from the PC version:
Source: Kojima Station, JunkerHQ, GeForce