Will there be levels of difficulty to choose from, and if so how will this affect the challenge based unlock system?
I have heard that the AI (in campaign) is meant to be of a similar standard to real players, if there are no levels of difficulty then surely some players will get pooped on by the bots as they would online and not progress with unlocks in challenges, and other players will find it very easy (just like in a Vs. game online) and not much of a challenge at all.

I believe there are three difficulty levels for the bots. Easy (as if playing against small children), Normal (as if playing against regular human players), and Hard (as if playing against omniscient robots from the future).

Or were there four difficulty settings? Need to look back through dev quotes... :homestar:

i think the bots have a set difficulty level, but as you lvl up they get access to better items, i doubt they'll be insanely hard and crush new players

Great question, I've wondered this myself. Like do you get better equipment for completing challenges (or even campaign) on the hardest difficulty or is it just for bragging rights. I'm assuming the latter.

Campaign gives you no unlocks but the challenges do and you do get better stuff for each different difficulty level.

I want to play on hard so I am forced to get better - I hate being [censored] at FPS games so it's best to learn while being punished , it's how I learned to be a semi good player at street fighter, lol.

That's pretty much what I did to get good at COD (as well as watching YouTube videos) but I think I will end up hating this game if I throw myself in at the most difficult level - I usually start on the 3rd hardest of 4, and that sees me right.