Yesterday we got dropped that image of a Bungie forums search menu, which tipped something called "Halo: Reach." Such things are easily faked, and I couldn't run it down. Well, now someone's found a cache of since-deleted Bungie forum posts on this subject.
As you can see, for a brief time there was a forum for something called "Halo: Reach." A 2001 novel called "Halo: The Fall of Reach" is official, canonical, and functions as the prequel to Halo: Combat Evolved. It was also the basis for a spec script Stuart Beattie wrote for a Halo movie. Also, back in September, Phil Spencer indicated four Halo "things" were in development, two being Halo Wars, the Halo: Chronicles project said to be linked to Peter Jackson. A third can be assumed to be Halo 3: ODST, announced about a month after that interview. So is Halo: Reach the fourth thing?