This is pretty much a repost of a suggestion I had earler.
My little group of friends and I would like to have the ability to chat briefly when declining an invitation. Could be in the middle of a good round, or just unavailable for however long. It would be nice to give a courteous reason, or set up a time frame. Several times a friend and I will play tag and end up not playing that day.
Someone mentioned the privacy matter. If there was an enabler for use only among friends that could be turned on and off, I don't think that would be an issue.