Some Halo 4 Game Informer Leak news
Multiplayer – It’s red versus blue.
Mulitipayer with take place on a 3km long training ship for Spartan IV’s (for reference, Master Chief is a Spartan II and Noble Team were III’s). Red Vs Blue must be a nod to the long running series by Rooster Teeth
Sprint is now a standard for everyone. The hologram, jetpack, and active camo will be making a return as well There is one new armor ability called Forerunner vision. It lets you see through walls.
There is no more respawn delay, this has been removed entirely in favour of immediate respawns in Slayer games.
Use Spartan Points for buying in game items. So basically Halo: Reach’s credits with a new name
Joining while games in progress
Sounds like you can avoid the lobby if you want!