Here's the thing about Google Instant: it's a rather nifty thing but that's not what is important. What is crucial is the introduction of 'a new kind of "conversational" search interaction'. So, now you can talk to the search engine. Microsoft tried this paradigm some years ago, I think, with some eminently forgettable avatar character and it was a fine failure (to be fair, the technology and research was not mature then). Google is now poised, I believe, to succeed.
A few key technical things have come together to make Google Instant happen, particularly speed and the ability to predict search queries on the fly. Google has been investing in this area for long and we are beginning to see some interesting results.
With Android, the Google Genie is now in your pocket. After this post I checked (using Google, naturally) if anyone has used 'Google Genie'. Someone has.
One last thought: Some day, Google will google itself.