I do remember quite earlier seeing this feature in yahoo search instant but then this was introduced in google search also quite earlier even though Google made a announcement just recently. Google instant will be of use to normal people like us who do search on popular search engines , but possibly more useful for commercial purposes and paid search.
What next after instant google .. google Now !!
Its like instant now , just like twitter and facebook
So what has google instant to ofer you , well its pop s up search options as you tye helping you to become a more lazy searcher and spoon fed if that is hat you like . some people will call it convenience and rightly so for some
Here are some snapshots of google instant while i am doing a search for google china , google australia and google UK
Lets watch some google instant in action


As per google.com
Google Instant is a new search enhancement that shows results as you type. We are pushing the limits of our technology and infrastructure to help you get better search results, faster. Our key technical insight was that people type slowly, but read quickly, typically taking 300 milliseconds between keystrokes, but only 30 milliseconds (a tenth of the time!) to glance at another part of the page. This means that you can scan a results page while you type.
more here : http://www.google.com/instant/#utm_campaign=launch&utm_medium=van&utm_source=instant
Ref:
http://www.googleaustralia.com.au/

http://www.mygoogle-baidu.com/
![]()
http://www.search-google.co.uk/

http://www.google.com/instant/

