"Most new features can be detected in JavaScript. To test for HTML5 video support, create a element and check for a property in its DOM: if("canPlayType" in $new("video")){...} See Chapter 2: Detecting HTML5 Features."
"Assuming that it'll be a while before most browsers attempt to implement most of HTML 5 (a perfectly reasonable assumption) we need to start thinking of ways to tackle the creation and rendering of HTML 5 components in the meantime. Obviously, using the tools of JavaScript and CSS we can accomplish a lot."
" Mark S. Miller explains how to create secure applications in ECMAScript 5 and HTML5 by turning JavaScript into a distributed secure programming language. "
" Michael Mahemoff discusses how HTML5 can be used to create single page web apps offering advice to create a better user experience, built-in accessibility and better SEO results. "
"The current product I am building makes heavy use of HTML5 & javascript to give the user a rich experience, both on and offline, across a variety of screens. Before I even started this application I knew I wanted a clean and proven approach to help manage the complexity on the client. After reviewing several js frameworks I decided to go with backbone.js (compare yourself). I have been working with backbone for several months and I am really happy with it, and would recommend to anyone building similar types of javascript applications."