If you’ve been participating in the Firefox 5 beta, pop open “About Firefox” to find a nice surprise. Whereas Mozilla has announced that the official release will come on June 21, final code is already available.

What’s new in this fast tracked development model release? With the exception of Channel Switching, pretty much all of the features that were part of the Firefox 5 beta:

• Added support for CSS animations
• Do-Not-Track header preference has been moved to increase discoverability
• Improved canvas, JavaScript, memory, and networking performance
• Improved standards support for HTML5, XHR, MathML, SMIL, and canvas
• Improved spell checking for some locales
• Improved desktop environment integration for Linux users
• WebGL content can no longer load cross-domain textures
• Background tabs have setTimeout and setInterval clamped to 1000ms to improve performance
• Firefox development channel switcher introduced in previous Firefox Beta updates has been removed

In order to get the release version of Firefox 5, you’ll first need to download the most recent beta seed and then update from within the app.

And, for those with a taste for danger, Mozilla’s Aurora (a.k.a. “alpha”) developer channel offers the chance to “Experience the newest innovations before they go to beta in an environment that’s not for the faint of heart.”

That said, with the release of Firefox 4, I switched back from Google Chrome. Whereas searchzilla’s browser is faster, Mozilla’s delivers better performance overall, especially when it comes to add-ons and extensions.

Are you a Firefox fan or has Chrome tickled your fancy?