Farhad Manjoo says the newest release of Firefox is so excellent it may change the Internet itself:
The best thing about the new Firefox is that it gives us a peek at the Internet of tomorrow. Since 2007, the World Wide Web Consortium, the international standards body that sets common technical definitions for the Web, has been working on HTML 5, an update to the coding language that defines every page you visit online. Although the consortium has yet to publish its final specifications for the new standard, many browser companies have been incorporating features of the language in their latest releases. Firefox 3.5 offers the best implementation of the standard--and because it's the second-most-popular Web browser in the world, the new release is sure to prompt Web designers to create pages tailored to the Web's new language. In other words, Firefox isn't just an upgrade for your computer; it could well prompt a re-engineering of the Web itself.
The best way to appreciate what HTML 5 can do is to install the new Firefox and run the collection of demos put together by Paul Rouget, Mozilla's European evangelist and a Web developer extraordinaire. Rouget's pages show off one particular aspect of the new language--its facility with video, which has always been a second-class citizen on the Web. Today, most of the clips you encounter online require plug-ins that you have to install alongside your browser; when you go to YouTube, for instance, your browser calls on Adobe Flash, the platform that actually knows how to play the clip.
HTML 5 will alter this process. Firefox 3.5 allows designers to add videos that require no third-party plug-ins; the clips, which can be coded in the open-standard Ogg format, are processed by the browser itself. This allows videos to become just as interactive as every other part of a page: You can rotate a video while it's playing, have a clip show up in a circular frame rather than a square one, or have a video respond to data pulled in from other parts of the Web.