I read in game informer a comment implying that master chief will move slower or jump not very high.
I have a huge issue with the news. Read it here if you want: http://www.gameinformer.com/b/news/archive/2012/02/17/343-talks-halo-4-master-chief-design.aspx
Here is the problem with this "logic" (statement contradicted itself as to why they are making the change)
1. halo separates itself from other first person shooters because of its fast paced physics. having fast paced physics is what makes the game skill intensive instead of strategy intensive like COD. why ruin halo for me 343?
2. the representative of you, who made the statements, introduced its thesis (masterchief will act like he weighs 800 pounds now) by stating how each halo game has slightly altered mc's armor, and therefore "here is our alteration." This is an absurd argument, because instead of changing how much mc weighs from 800 to something else (changing his armor), you are changing SOLELY how mc reacts to his armor weight. This will contradict all of the halo backstory about how he has surgical, genetic, and hormonal augments which has been clearly states as the reason for why 800 pounds just "aint that much baby." Or how about this solid argument: his armor reacts to his neural impulses and multiplies all of his movements. <----- Stated in the halo books by author eric nylund.
So throw this fast paced gameplay out the door, the gameplay that made halo the ultimate multiplayer shooter. What are you left with? Sounds like a straight B-rated game that banks on the built in fan base