http://www.xbox.com/en-US/games/h/halo3/promotions/buyxboxgethalo.htm?WText.camp=Games&WText.campSrc=RSS
Read the Requirements Below! New Live Account and purchase made between 11/21 and 12/21.
UPDATED: WARNING THEY CHANGED THE REQUIREMENTS! Below is the orginal promotion posting from this morning. The site now states you have to be a original xbox owner with paid live account and convert to xbox live gold account after purchasing new 360. Why the hell are you going to offer a promotion to a small portion of leftover holdouts? Crazy...
Published November 16, 2007
If you're more than ready for Halo® 3, but still have an older console, here's the plan for you. Buy your Xbox 360® before December 21, 2007 and we will give you a copy of Halo 3*. Finish the fight in high definition, with new weapons and challenges. Join three friends in Campaign mode, or get an Xbox LIVE® Gold subscription for sixteen-person multiplayer action.
Free Halo 3? It doesn't get any better than that.
Here's How to Get Your Halo 3 Game
(*Online offer valid in the 50 United States, D.C., and all United States military bases with valid APO/FPO bases. Offer expires 23:59 hr (PST) December 21, 2007. You must purchase a new Xbox 360 system between November 21, 2007, and December 21, 2007, establish a new Xbox LIVE Account, then register on the promotion website on or before December 21, 2007. Hard drive, Windows Live™ ID, and high speed Internet access required for Xbox LIVE account. (See Xbox LIVE system requirements at www.xbox.com/live.) Limit: one offer submission per person. Xbox 360 Halo 3 game will be fulfilled through mail by January 18, 2008. Fulfillment requires a valid mailing address. Not combinable with other Microsoft offers or rebates. Proof of purchase required.)
Read the Requirements Below! New Live Account and purchase made between 11/21 and 12/21.
UPDATED: WARNING THEY CHANGED THE REQUIREMENTS! Below is the orginal promotion posting from this morning. The site now states you have to be a original xbox owner with paid live account and convert to xbox live gold account after purchasing new 360. Why the hell are you going to offer a promotion to a small portion of leftover holdouts? Crazy...
Published November 16, 2007
If you're more than ready for Halo® 3, but still have an older console, here's the plan for you. Buy your Xbox 360® before December 21, 2007 and we will give you a copy of Halo 3*. Finish the fight in high definition, with new weapons and challenges. Join three friends in Campaign mode, or get an Xbox LIVE® Gold subscription for sixteen-person multiplayer action.

Free Halo 3? It doesn't get any better than that.
Here's How to Get Your Halo 3 Game
- Buy an Xbox 360 console by December 21.
- Connect to Xbox LIVE.
- Register HERE with promotional code XBX7777, your new console serial number, and a valid mailing address.
- And look for your copy of Halo 3 for Xbox 360 in your mailbox!
(*Online offer valid in the 50 United States, D.C., and all United States military bases with valid APO/FPO bases. Offer expires 23:59 hr (PST) December 21, 2007. You must purchase a new Xbox 360 system between November 21, 2007, and December 21, 2007, establish a new Xbox LIVE Account, then register on the promotion website on or before December 21, 2007. Hard drive, Windows Live™ ID, and high speed Internet access required for Xbox LIVE account. (See Xbox LIVE system requirements at www.xbox.com/live.) Limit: one offer submission per person. Xbox 360 Halo 3 game will be fulfilled through mail by January 18, 2008. Fulfillment requires a valid mailing address. Not combinable with other Microsoft offers or rebates. Proof of purchase required.)