History of Social Meida

I found a modern, engaging, and interactive website providing the history of social media:

http://avalaunchmedia.com/history-of-social-media/Main.html

It is interesting that this site begins social media with the postal service.  Some 'experts' debate that social media must be include the internet, and suggest that social media began with the first online forum.  Others argue that social media first began with pigeon posting, in which pigeons would fly messages from one location to another.  From my research, I tend to believe that pigeon posting was the first advent of social media.  While the definition has now evolved to include the internet, the first definition and examples seem to date back to pigeon posting.