The official Army of Two: The 40th Day website has been updated with a new developer diary talking about the reasons behind developing the title in Shanghai, China. Army of Two: The 40th Day is due out on January 12th, 2010 in North America on the Xbox 360, PS3, and PSP platforms.

From the developer diary:
‘In Army of Two: The 40th Day, Salem and Rios fight their way through Shanghai in order to survive as the city is destroyed by the 40th Day Initiative. The decision to set Army of Two: The 40th Day in Shanghai was ultimately crucial in developing fun gameplay and an intriguing story, and as you will see it will be an all around…’

Check out the full developer diary at the game’s official site.