Google is busy in testing the new search interface which allows you to update your search query the way you type. In this experimental test of new search interface you never have to type your query and press Search/Enter button.
This interface have a advantage to the previous search as it is much faster and refine your search query at once you type your keyword, where as the constant refreshing and changing keyword feels quite annoying to some of the users. According to Rob Ousbey he names the experiment as “live updating Google search results” while Google uses the word “Streaming” and some say it is an “Incremental search”.
The experiment has not yet been deployed at Google Labs, but you can can experience the interface via Google Alerts, all you have to is type a keyword, click on “Preview results” and you will get the results then and there, now change the keyword and your search result will start changing as your keyword changes. Similar to this is Keyboardr, another search site with similar functionality which uses Google AJAX API to display results.
For further detail watch the video below: