Honestly jokolo, learn to use something called your brain. Stickied thread, bright blue, says "HALO? PUT IT HERE JOKOLO! FRIGGIN PUT IT HERE AND DON'T WASTE UP SPACE!"
The only new things were a couple of new online maps, new story, new campaign, firefight, and you're not Master Cheif.
It's just another Halo. They stole firefight from Gears of War, just added a new campaign, new online maps, and done. Bungie is just milking the series.