Rated 3 out of 5 stars
For those of you who want this add-on, but are not happy being saddled with Yahoo! as the default search engine, you are not alone. Fortunately, there is a solution.
1. Open a new tab or window.
2. Type 'about:config' in the address bar.
3. Click [I'll be careful, I promise!].
4. In the Filter, type 'keyword.url'.
5. Double-click the URL below Value.
Paste one of these URLs:
(I included this for fairness' sake.)
Windows Live Search: http://search.live.com/results.aspx?q=
6. Click 'OK'
Your default search engine has been changed.