Is that real?^^

The pre-orders bonuses are real, but the video itself is fan made.

Information on the railgun from bs angel ( halo waypoint):

The Halo 4 Railgun

Halo 4’s arsenal includes numerous weapons, some of which you’re familiar with, and others of which you are not. One of the all-new aforementioned items you’ll have at your disposal in Halo 4 is the Railgun. Manufactured by Acheron Security, its official designation is the Asymmetric Recoilless Carbine-920.

The ARC-920 Railgun is a compact-channel linear accelerator that fires a high-explosive round at incredible speed, delivering both kinetic and explosive force to hard and soft targets alike. (Insert discreet cough here.)
Like the Spartan Laser, the Railgun has to be charged before firing. There are appropriate (and awesome) audio cues when that’s happening. The Railgun’s charge time feels like approximately half of the Laser’s.

One of the more notable differences between the Railgun and the Laser is the Railgun does not have a zoom function. While I initially saw that as a negative, it turned into a positive because the lack of a zoom function eliminates those moments when you’re making an adjustment, someone shoots you and pulls you out of zoom, and you end up overcorrecting and missing your target. The Railgun offers more of a static experience where the corrections you’re making, whether someone is shooting you or not, are going to be the same. If you move left, the reticle is going to stay to the left. If you move right, the reticle is going to stay to the right. Ultimately, it lets you muscle your way through taking fire, allowing you to be clutch with a one-hit kill weapon.

The Railgun does not do as much vehicle damage as the Laser, but strategically placed shots are able to change a vehicle’s force and direction. When its projectile hits a vehicle, it has the potential to send it flying, rolling, or perhaps even off a cliff because of the kinetic energy (similar to repeatedly hitting a Warthog with a Brute Shot).

Once the Railgun has been fired, it feels instantaneous; the moving projectile doesn’t feel like it has a lot of travel time (think Rocket Launcher vs. Laser). Overall, in its current iteration, it’s considered a power weapon as it is super lethal and deadly accurate. When the game ships, though, it may end up shooting marshmallows. Marshmallows of death, doom, and destruction, but marshmallows all the same.

Seems nice!

Some leaked ( although blurry) images!

Halo 4 leaked gameplay! It's bad quality, but it is something. New weapons and assissination!
http://m.youtube.com/#/watch?desktop_uri=%2Fwatch%3Fv%3DBPhhb1gidPg%26t%3D1m37s&t=1m37s&v=BPhhb1gidPg&gl=BE

... The quality and "music" make me want to puke, I'll wait for E3, even Halo isn't worth listening to that... Cheers for sharing though.

Lol at youtube comment, "What model of potato was this filmed with?" :P

one more week!

Wake me when you need me E3 is here!

Anyways, from what I can see the assasination looks awesome!