The latest Firefox 4 is considerably faster and boasts some welcome features with minimal look. Now the address bar has changed to omni bar ( combination of address bar and search bar, similar to Google Chrome), which means, you can type in a web address as usual or keyword you want to search for in the address bar.
The default search provider for Firefox 4 Omni bar is Google, and there is no easiest way to change it to Bing, Yahoo or any other search engine without tweaking about:config page manually.
How to change the default Firefox 4 address bar Search Engine:
Hope you’ll enjoy this simple post. (via)