Here is some background on the game.
LucasArts today announced that their hit video game Star Wars: The Force Unleashed will see further expansion this Fall through a new downloadable level for the Xbox 360 video game and entertainment system from Microsoft and the PLAYSTATION 3 computer entertainment system. In addition, the company also announced Star Wars The Force Unleashed: Ultimate Sith Edition, a special new version of the game for the Xbox 360 and PLAYSTATION 3, that will show gamers the deepest, darkest side of the Force in a story that puts them on a collision course with Luke Skywalker himself. Available this holiday season at retail stores, The Ultimate Sith Edition will include all of the original missions found in Star Wars: The Force Unleashed as well as content previously only available via download and an all-new exclusive bonus level.
The mission begins at the end of the story of The Force Unleashed and re-imagines the Star Wars Saga as if the Secret Apprentice had killed Darth Vader and taken his place at the Emperor's side, becoming the most powerful Sith Lord in the universe. The story picks up as the Emperor sends his new apprentice to the planet Tatooine to dispatch Obi-Wan Kenobi -- who has been hiding on the planet ever since the events of Star Wars: Episode III Revenge of the Sith. During their hunt for the reclusive Jedi, players will also explore the depths of Jabba the Hutt's palace and encounter notorious bounty hunter Boba Fett.
The exclusive level concludes the "Infinities" storyline set up in the Tatooine mission, as the Secret Apprentice is sent to the planet Hoth on a crusade to crush the Rebellion once and for all. While on Hoth, players face Luke Skywalker himself while visiting iconic locations seen in Star Wars: Episode V The Empire Strikes Back.
From what I read, more can be learned at this site:
http://www.theforceunleashed.com/
