In 2004 the KM Clusters conducted a special leadership retreat in London focused on enterprise and commercial applications of social media.  Here are some interesting data.

Google Scholar mentions of ‘social media’ 1900 – 2009.

•     1900–1980                       88 mentions
•     1980–1990                       77 mentions
•     1990–2000                       384 mentions
•     2000–2003                       393 mentions
•     July 2004 London KM Cluster on Enterprise Social Media
•     2004-2009                        4270 mentions

The rest, as the saying goes, is history.