The third episode has been released for Halo 4: Forward Unto Dawn.
Halo 4: Spartan Ops Extended Behind the Scenes
343 Industries and Axis Animation talk about creating the unprecedented Spartan Ops content for Halo 4.
Halo 4 Trailer VFX Breakdowns by Method Studios
Method Studios do VFX breakdowns of several scenes from their recent cinematic trailer for Halo 4.