Finally! Details! On a Bungie Halo title! Courtesy of Microsoft's TGS address, the Halo 3 singleplayer expansion - first revealed in a trailer a few weeks back - now has a name (Halo 3: Recon), a setting and a rough release date. The expansion will serve as a prequel to the events of Halo 3, with the player taking the role of a UNSC recon soldier, who is our "new hero" for a "new campaign". The expansion will be out in "Fall 2009", with screenshots and video expected sometime soon.
UPDATE - aaaannnddd we have a trailer.