Mozilla re-introduces it Test Pilot for Firefox, one Plugin which allows anyone to try the experimental features and report their impressions.
The Test Pilot first introduced for Firefox 3.5, but now the updated program contains three key components: Activity Stream, Tab Center, and Universal Search.
The Activity Stream aims to make your browsing history search faster, which Mozilla believes will help you find important websites and view content faster. When you open a new tab, Activity Stream checks your top sites from your browsing history and their bookmarks you.
The Tab Center it is fairly simple: displays the open tabs vertically and along the left side of your screen and not horizontally and at the top of the window.
As far as Universal Search Mozilla says it “combines history with the Search drop down menu to give you the best recommendations so you spend less time searching through results search. "
Currently Test Pilot is available in English, and you can download it via it testpilot.firefox.com