I might not have these all correct, but this is reasonable accurate:
We divide the internal team into three "domains" - MX (merchant experience, admin panel stuff like defining products, etc), CS (Customer/Consumer Services - the web store front), and PS (Platform Services - stuff sup porting both, like caching and the installer). So if we think something is for one of the domains, we add a label to help track it. DOC is for docs team.
Looking at the rest, I think the names are pretty self evident. If not, let me know which one you don't understand.
