Glenn starts out by going over the history of Javascript, its start from a (from the slides)
10 day hack that got shipped (We could tell)and the time it was considered a nuisance that was mostly used to create ads and other things in the browser.
However, while Javascript wasn't too popular in the browser for a long time, Glenn points out how it got embedded in other systems, such as Flash, Acrobat, Widget libraries, or the Mozilla platform, before it's resurgence with the AJAX boom.
Glenn continues to detail the merits of Javascript, such as it's prototype-based OOP system and more. Building on that, he shows how powerful libraries such as jQuery, Prototype, and others make use of the powerful tools that Javascript provides.
Watch Glenn Vanderburg on "The Overlooked Power of Javascript".