I think if it was set up so you can only hear those you choose to hear, and the rest go by regular chatting, I don\'t see why it wouldn\'t work. Sometimes (when multitasking) it would be much easier to talk to someone, and also when you try to explain something to them.
Of course, you wouldn\'t want to be able to hear everything everyone says, only those you choose to. Don\'t have a headset, people can still just text you. I see no reason why they couldn\'t incorporate it, but I also don\'t see a really good reason for them to do it either. It really has no advantage or disadvantage IMO.