[pedrokost]

Google Instant will make Google's Web History less useful (if it was of any use before) and easier to trick, since the History records only if you actually press Enter after the query or if you click a results. However a lot of information can be revealed from the description of the results that Google offers and so people won't always have to click Search to get the info they required.

[ugh]

It also remembers when you were looking at search results for more than three seconds (it will even distinguish between normal searches and those three-second things). Unless you can be done in less than three seconds you cannot trick Web History.

[xiongchiamiov]

With link-hinting, it's quite possible to be off the page in under 3 seconds. Of course, the percentage of Google users who use link-hinting is... very small.