IE7 and Firefox 2 come with a new search toolbar which allows you to select the search provider, ie., Google, MSN, Yahoo, etc.  The toolbar allows you to find more providers, but you really want to start adding vertical search engines, customizing your searches, add different languages, then check OpenSearch:  adding search to IE7 and Firefox.  It's a lot more powerful than the standard list and allows the end user to  add search providers or plugins to the new browsers.