Halo 4 Review

Halo 4 is an upcoming first-person shooter video game and the eighth installment in the Halo franchise being developed for the Xbox 360. Halo 4 is intended to be the first of a new trilogy of Halo series games, named the "Reclaimer Trilogy". Whereas the previous Halo games were developed by Bungie, Halo 4 will be developed by 343 Industries. The game begins 4 years after the ending of Halo 3, and marks the return of the Master Chief as the main protagonist, and the AI Cortana.
Halo 4 was officially announced on June 4, 2011, at E3 2011. Its development was revealed at the same time as Halo: Combat Evolved Anniversary. The game is set for a worldwide release on November 6, 2012.

Gameplay

Modes

Halo 4 will feature a new story-driven game mode, titled "Spartan Ops", it can be played solo or cooperatively with up to three other players. It serves as a replacement for the Firefight game mode that featured in Halo: Reach and Halo 3: ODST. Season 1 of Spartan Ops will deliver 5 new objective-based missions and cinematics each week over a period of 10 weeks to players.
Halo 4 will also include Forge, a map-editing tool, that was first featured in Halo 3.
If any story ever seemed to exemplify the dangers of trying to be too clever when teasing your fans, it could be this one. Because unless this is all an elaborate red herring (and to be honest, there's a decent chance it might be), then Halo 4 developer 343 Industries might just have accidentally leaked a fairly significant page of the game's script all over the internet. 

Originating in a post on NeoGAF (potential spoilers through that link obviously), the story goes that a raft of information regarding a (or potentially the) climactic battle with Halo 4's previously unconfirmed antagonist is visible during one brief shot in 343's recent "A Hero Awakens" documentary video. A re-watch and some judicious pausing reveals that the information is indeed present, via what appears very much to be a page from the game's mocap performance script.