I've found that I can add someone to the CC list when I create a ticket, but I don't have permission to add someone to the CC list after the ticket is created. So far, I see no reason to not allow registered users to modify the ticket CC list. It can be useful too, because I was chatting with someone on IRC today, and told that person I would CC them on the ticket for the issue we were discussing. Does anyone see a reason to not allow this?
We previously discussed on this list that committers would have MILESTONE_ADMIN as well. I suggest we follow through with granting that permission to committers now unless someone has a good reason to not do so. - Ryan
