Source: http://www.gamedaily.com/articles/news/empire-total-war-shifted-to-march-2009/
You'll have to wait to conquer your own empire until this coming March. The good news is the extra time will allow The Creative Assembly to implement a multiplayer campaign mode.
by David Radd on Friday, December 12, 2008

Sega representatives announced today that Empire: Total War's release date has been moved to March 2009. This time will allow developer The Creative Assembly to implement a multiplayer campaign mode. All of those who pre-order the game will have access to the one-on-one multiplayer campaign mode beta.
"The extra development time will allow us to finalize and polish Empire, making it the most accomplished and epic of the Total War series." said Kieran Brigden, Studio Communications Manager at The Creative Assembly. "There is a great deal of anticipation around Empire: Total War and we want to ensure that it is the benchmark for strategy games upon its release."
Well it looks like they will take their time on this one instead of rushing it out which, after all, is a good thing for everyone ;)








