Creative Assembly are bringing modern weaponry to the world of Shogun 2 in a new stand alone expansion that covers the 19th century period of Japans emergence into the modern world.
Shogun 2 : Fall of the Samurai aims to be the biggest piece of content thus released for Shogun 2, and will add new modern warfare aspects such as ironclad warships, railway networks, and shore defences. For the first time also Naval and land combat will be able to interact with shore bombardments and coastal gun emplacements available to the player. Western nations America, France and Britain will also appear in the game but apparently not as playable factions – CA have stated only that six clans will be available to choose from.
Also in the works is a major update to multiplayer with a new conquest map, new avatar and new additional avatar content. You will also be able to have multiple avatars now.
Fall of the Samurai is expected to be released in March 2012.
See this CA blog for more information.