It would be mere rumors and speculation at this point, but a supposedly reliable source has confirmed with Joystiq that "Halo: Combat Evolved" will be getting a complete do-over with new visuals, art and gameplay mechanics. The "Halo" remake will be released during the holiday season exclusively for the Xbox 360.
The source informed the site that the audio in the game would remain untouched, although the game would be running on a new engine, and not the one in "Halo Reach". Controls remain the same, and the game is expected to support resolutions up to 1080p and 3D. Multiplayer co-op is likely.
The game is rumored to be in development at Saber Interactive now that Bungie has left the house.