I would just like to make a post (which will hopefully be pinned) of all of the Halo 4 items and characters that are confirmed. Already we see a lot of new weapons and enemies.
Weapons
Assault Rifle -
Battle Rifle -
Sticky Detonator -
Designated Marksmen Rifle -
Magnum -
Rocket Launcher -
Sniper Rifle -
Spartan Laser -
Plasma Pistol -
Storm Rifle -
Needler -
Energy Sword -
Covenant Carbine -
Forerunner Scattershot -
Forerunner Light Rifle - No good pictures yet
Machine gun Turret
Plasma Turret (each seen in Spartan Ops)
Shotgun (seen in RvB Save the Date)
Promethean Grenade - Spartan ops gameplay. Some sort of static grenade.
Gravity Hammer? - If grifball comes back, the hammer will have to as well...right?
Vehicles
Warthog -
Mongoose -
Ghost -
Banshee - No decent picture
Enemies
Grunt -
Jackel -
Elite -
Promethean Crawler -
Promethean Watcher -
Promethean Knight -
As for the new Forerunner enemies, I strongly believe they are only machines, and not actual forerunners. They don't match any of the forerunner descriptions, and Cortana did say (It surely is non-organic)
I also didnt post pictures of the Covenant Enemies since I dont have the ability to post that many pictures at once.
If you find any pictures or other details, post them below and I will add them up here.