Andylew - 9:23 am on Oct 20, 2010 (gmt 0)
One thing I have noticed is you get a nice little blue arrow pointing to the top AdWords ad (as long as there are ads above the organics) after you have entered your query and hit enter or search.
If you arent aware, if you then use your direction keys this arrow moves to select a result then hit enter to navigate to it - anothe gimmic which even some people in the industry dont even know about! There is a topic on it I think.
Google instant is a complete gimmic, for many of the reasons already mentioned. It would of course get a thumbs up for cleverness which could be why it got through the panel of testers but the practical applications are slim to none to the wider searching audience.