Microsoft has let it be known that Halo 3 is indeed getting an expansion and it'll be dropping from orbit sometime in the fall next year.
Set before the events of Halo 3's main story the player takes control of a "new hero in the Halo universe," a UNSC marine. It adds hours of new gameplay and multiplayer too.
Recon is due for release early next year and is a standalone expansion for Halo 3. "This new chapter in the Halo saga lets you experience events leading up to the epic story told in Halo 3 through the eyes of a new hero in the Halo universe," say Microsoft.
"The Halo 3: Recon campaign is an intriguing side story that takes place during the terrifying events leading up to the Master Chief’s return to New Mombasa in Halo 3."
Not sure how Bungie and Microsoft plan on distributing the game or how much hard cash they want to pry from you yet. Check out the screens below: