If you take a look at recent interviews from the 343 crew, you will see mention that Halo 4 is going to contain a certain type of “perk” system. While we don’t yet know what that means here are some key quotes.
> And there will be perks, a new way to customize your Spartan IVs armor changing not just the look, but their balance.
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> While these armor upgrades were seen in Halo 3 and Reach, they’re no longer solely cosmetic. Perhaps in deference to the booming trajectory of the Call of Duty titles, for the first time, a Halo game will feature a persistent upgrade system that directly affects gameplay.
and
> “What we do take very seriously is changing player habits,” he said. "So rather than chasing Call of Duty or Battlefield and trying to do their thing and doing it poorly and doing injustice to it, we’re trying to do our own thing, and do something fairly original but still something that’s completely compatible with the Halo universe.
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> "Halo’s not Call of Duty. Halo’s a sandbox game about really emergent things. A lot of things that worked great about Call of Duty – and don’t get me wrong, I was addicted to Black Ops all of last year – they do player rewards really well. We’re not trying to do the same thing, it’s as simple as that.
So, while the true affect of these “perks” remains to be seen, do you really think they belong in Halo 4? I personally feel like Halo 4 needed to return to a standard arena shooter (ie: everything you play with appears in the arena; there are no balance issues created by weapons, upgrades, etc., that a player can spawn with).