The recently announced Dark Souls: Prepare to Die Edition, a PC port of the popular high difficulty action game, stirred up much controversy and outrage amongst fans for only staying with Games for Windows Live. However, the popular Demon's Souls sequel is now being released on Steam as well.
The game will be coming to the PC on August 24th, which includes all the content of the original console release plus additional content, such as more bosses, more enemies, and more weapons.
For console owners however, you can buy the additional content as DLC when the game is released. Named "Artorias of the Abyss", this additional content will cost $15 for both the Playstation 3 and Xbox 360 versions.
Source