Angular is what HTML would have been had it been designed for web apps. In this presentation, MiÁko Hevery, from Google, and author of Angular is going to show you what it's all about.
To quote the description from the HTML5 Developer Conference:
Angular allows you to extend the HTML vocabulary, have proper business-logic / presentation separation through bidirectional data-binding, declarative application assembly through dependency-injection, and testability story like no other framework. Angular is a fundamentally different way of building an AJAX app.