I've been using Joomla since the Mambo days but more intensely over the last few years after setting up BarclayWorks. I'd consider myself an expert user but love the fact that there is always something more to learn, especially at the moment with the advent of a new version.
I'm an active participant in the London Joomla User group. If you would like to know more about this: http://www.joomlalondon.co.uk/
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