True to its word, Mozilla is wasting no time releasing new iterations of its popular Firefox browser. The global, nonprofit organization announced today (June 21, 2011) that it has released the latest version, Firefox 5.0, for Windows, Mac, Linux and Android. Though Firefox 5 contains over 1,000 bug fixes and performance enhancements, most users shouldnt really notice any major changes. Firefox 5 for Android actually does add one pretty major feature: Do Not Track. First made available in Firefox 4 on all desktop platforms, the feature took the form of a small checkbox under Advanced preferences, and it read as follows: Tell web sites I do not want to be tracked. Websites small and websites giant, including Facebook and Google, rely heavily on tracking users browsing history to deliver targeted advertising. Checking the box wont actually prevent publishers and advertisers from tracking users, though there are ways of doing this (see: Adblock). Its more of a polite request that may or may not be respected. While with Firefox 4, Do Not Track was only available for desktop platforms, Firefox 5 makes the feature available on Android as well. Other updates include a new Firefox Add-on SDK for Windows, Mac and Linux that enables local development of add-ons and a Firefox Add-on Builder Beta for a hosted Web-based build environment. The new Firefox also supports the CSS Animations standard. Firefox 5 arrives on the scene just three months after the launch of Firefox 4. The browser was downloaded over 200 million times, but it was seen as the end of an era where users had to wait long multi-month or -year periods in between browser updates. With more heated competition, especially from quickly-iterating Google Chrome, Mozilla has been forced to bring its release cycle up to speed. Before Firefox 4 was even released, we were told wed see four new versions of the browser before years end. Were now halfway there.