Credits, ranks, and commendations are coming to Halo: Reach
but what do they do? Well, Blizzard explains it all in this weekly update
that gives you a ton of information and screenshots from the beta. Credits are like experience as you earn them and level up in rank as you earn enough but you can use it to purchase items as well. What's interesting is that items you purchase with credits you earn are purely cosmetic.
The also give their thoughts on how to combat boosters which I hate in any multiplayer game. I don't know how many times I get requests in Modern Warfare 2
on joining a server for boosting sakes. I'd like to earn everything I get the legit way, thank you very much. But I digress. Check out the update for your weekly Reach