I think you mean a photo of yourself, rather than an Avatar which is a graphical image of a users alter ego or role play..... here, I think we want to put photos that will remind us of whom we are conversing with!!
You are quite right Gordon - that's exactly the point! I tried to change mine to a photo but I was unable to. I deleted the old one - added a new one in its place but the old one returned.
We all know what Chris means. And anyway, according to my Mac dictionary, avatar has more than one meaning, and one could certainly be a photograph. By the way, my avatar is way out of date but I rather like it!