Developer Techland will be putting out three pieces of downloadable content for Call of Juarez fans, with the first two set as map packs for multiplayer.
The third piece however is for singleplayer, and presumably wedges itself into the 'Extra Missions' section on the main menu. The DLC will be for Xbox 360, PS3 and PC versions.
Polish site Polygamia claims that the singleplayer DLC will be laid out exactly like the two open world sections in the game. The Wild West is one of the lacking backdrops in videogames today, but that's starting to change.