It would depend on how easy it is to setup.
That said, I think it would be best used by those in a realm, religion, guild, or tournament.
I think region would be too small an area, though there are times it could work very well. When vast armies are arrayed together, bringing up a chat and just talking could be fun.
I can certainly see the positives of the idea. The issue would be how difficult it would be to implement. If too difficult, I agree with the idea of not doing it. If I way can be found to make it easy, then I think it would be an excellent tool to use.
