While it isn't necessarily any more vague than when it's done or any of the other non-release dates release dates that developers give out when they don't want to try and pin themselves down to a specific date, Microsoft has put up a page with general information about Xbox games, including Halo. Like all the other Xbox games mentioned on that page, the release date is listed as Holiday 2001 . Of course, there is no mention of which holiday that is, so it could be anything between Halloween and New Year's Eve, I suppose. However, given that the Xbox itself won't be out until November 8, smart money is on sometime between then and the start of the Christmas shopping season around Thanksgiving or so.
Speculation all along has been that Halo would be a launch title , and some have suggested that the game might even be bundled with the console-- but I'd bet against that. Halo is likely a good candidate for being the premiere game available at or near the Xbox's release, and it'd be foolish to give up the extra sale. Remember what Atari bundled with the original 2600 VCS at launch? Yep... Combat, or as the Brunching Shuttlecocks put it, Invisible Tank Pong. What Xbox title currently in development gets to play that role, we don't know-- perhaps a secret project like Raven's Robot Roundup or something.