Had 1.5 million preorders before its release, making it an Xbox "Platinum Hit" months before it was even released.
In the series "Red Vs. Blue", a glitch in the first Halo: Combat Evolved (2001) that made characters aiming and looking down appear to be looking forward was the only reason that Red Vs. Blue could be made. This glitch allowed the early machinima artists to make the characters face each other and converse with their guns down and out of the way, although it was challenging to move appropriately with only a view of the floor. In Halo 2, the glitch was fixed and Bungie allowed players to lower their weapons by tapping down on the directional pad regardless of where they are looking.
Although the game was critically acclaimed, the developers felt that it could have been better. In a 2007 interview with Edge magazine, it is noted that they didn't have time for their customary "polishing" phase of development. A commentary for the game, featured in the Halo 3 (2007) "Legendary Edition", elaborates on this, describing sections of the game which had to be dropped in order to meet their deadline. The game would have continued past the much-maligned "finishing this fight" cliffhanger, to a final level on the Forerunner space ship.
The largest trailer for this game was released in movie theaters. Near the end of this trailer, the usual www.xbox.com URL is replaced with "www.ilovebees.com" for a moment. If someone goes to the website, they encountered a website which seemed to be under the control of a Halo-type artificial intelligence. This website continued to change, eventually telling a multifaceted story which explains how the Covenant find Earth in Halo 2, despite not knowing its location during the events of Halo 1.
Made $125 million in its first day of release, beating Spider-Man's 3-day record.