At J and Beyond 2012, I talked to Daniel Dimitrov, one of the excellent Joomla developers I have come to know during the last years. Hunched over the bar, we discussed all things Joomla, and he told me that he planned a series of Joomla related webinars. He felt there is a need for a masterclass type learning environment for those who want to learn more about Joomla.
As a developer, the most obvious for Daniel was to start by offering an Extension Development webinar. Since JAB, he's been working hard on the concept and now it's a reality!