I am going to try and compile an FAQ for the challenge system so please keep it on topic and questions about the challenge system and I will do my best to answer the questions and keep them organized for people to see information.
Here is a blog post by Nathan Plewes describing what the challenge system is.
If you wish to add a link to your mainfest in your signature block, a helpful fan has provided instructions in a thread linked here.
Also I can not comment on anything that is future, this is only for what is currently there.
Q: How do I unlock banners?
A: Completing the gold level of a challenge
Q: Do assists count?
A: Yes they count for both kills and assists for any point based challenges
Q: Are there any rewards for challenge points except banners? And names i think?
A: Those are the only current rewards
Q: Will weekend promotions run on the challenge system?
A: Yes that is the design
Q: Will there be promotional challenges that are only open for a short amount of time?
A: Thats the plan
Q: My account doesnt display the right Origin ID/GT/PSN ID under the N7 HQ.
A: Click on activate online accounts inside my games
Q: Why isnt <X> in the challenge system?
A: Some abilities don't work well with the challenge system so they arent part of
Q: Why isnt <X> gun in the challenge system?
A: We may add them later you'll have to wait and see
Q: Why isnt the challenges retroactive?
A: To give everyone an equal footing and there was no way to keep track retroactively?
Q: Why does it show that I dont have achievements for DLC?
A: We are looking into this
Q: Resurgence doesn't show up as a weekend challenge
A: Technically resurgence only required you to have the dlc installed, it used a different system we are looking at a way to display it for people but as of right now it is expected you dont have it
Edited by Bryan Johnson, 12 October 2012 - 03:42 PM.