This version allow you to import profile from Google Chrome browser. Not only that, Firefox 11 has an ability to adopt Google SPDY protocol. That mean, it will increase browsing time when accessing site which contain apps from Google. The claim said that the feature (SPDY) will increase browsing speed until 64%.
To activate the SPDY protocol, type about:config in Firefox address bar. Look at network.http.spdy.enabled, set it into “true”. You'll see the difference when accessing your Gmail inbox. Always get the latest Firefox in getfirefox.com.