Firefox 7.0 Released
 

Firefox 7.0 is the first stable release to benefit from Mozilla's "MemShrink" initiative, which aims to improve the browser's speed and resource usage by reducing memory requirements and addressing memory leaks that can bog down the browser over long sessions, or for users with many tabs open simultaneously.

Other new additions include a new version of "Canvas," a Direct2D acceleration feature for HTML5 games and animations; support for the W3C navigation timing API, which can help developers measure page load time under a variety of different circumstances; and Telemetry, which can send anonymous information about your browsing sessions to Mozilla to aid in the identification of performance issues. Upon installing Firefox 7.0, you'll be given the opportunity to opt-in or opt-out of Telemetry.

http://www.anandtech.com/show/4883/firefox-70-released