Firefox just launched its fifth Firefox 4 beta, which includes a more streamlined interface, faster graphics and a new audio API that exposes raw audio data (see video above).

What’s new in this latest iteration of Firefox?

* The introduction of an audio API which uses HTML5, allowing developers to visualize the sound data in a browser and creating novel ways to experience sound while web surfing.

* Emphasis on faster graphics with default graphics support from Direct2D, a 2-D graphics API for Windows 7, on machines that support Windows 7.

* Implementation of the HTTP Strict Transport Security (HSTS), a security protocol that increases the chances for a secure connections.

A stable version is set to be released by Mozilla in November. You can try out the latest beta here.