Firefox 5 Beta
Mozilla recently release Firefox 5 beta. It is recommended for advanced users who want to test the browser and are good at dealing with bugs and reporting them.
* “Do Not Track” option which stops companies from tracking your web history.
* Switch between different firefox versions, so you can from the release version to the beta version in a snap.
* More support for CSS animations and HTML 5 for websites that use that instead of Flash.
* Better support for Linux operating systems.
* THe ability to pin sites to the taskbar so you always a tab ready for your favorite site.
Source used: Business Insider.