I think you may be confusing Mojang implementing a feature, and Mojang putting easier tools in the code FOR a feature. They have already added lots of things that aim towards groups/teams/parties but they are 'deep in the code' and have to be implemented code side to be utilized in game.
I have to say being in a group as already helped me by allowing information to be passed to multiple specific people from several different frontier settlements saving me even a little time as apposed to retyping everything for each person. I could see this feature being used so that each member of each settlement can "privately" chat while newcomers visit to decide if they want to stay, or trade, or whatever other activity the settlement can offer. *Cheers!
So, this is basically becoming factions? Factions are cool and all but too much. Not the biggest fan of factions.
As boozle628 mentions above. No "GROUPS" are not like factions. Unless you are saying that any type of "group" in Minecraft are automatically like factions. By face value, YES they are both groups in Minecraft. But the concept, purpose, and implementation of both is completely different. I could come up with some confoodled metaphor displaying how they are completely different but that example will be flawed and would prefer not to embarrass myself for that. In other words - NO, not like factions not sure if ^^^ made any sense...
