I used Mambo for about a year before 2005 when the Joomla! project forked out. I decided to take the new road with Joomla! and have been using it ever since.

Interestingly enough, although I was using Joomla! for a long time I only got involved with the project more seriously once I attended my first social JUGT (Joomla! User Group Toronto) meeting last April.