I've just come across an interesting site released by Google. It shows search trends for 2008 and their correlation to politics, economics and so on.

Here it is http://www.google.com/intl/en/press/zei ... index.html

As you know in the end of the year Google posts its Zeitgeist, i.e. trends in searches. Check it out for 2009: http://www.google.com/intl/en/press/zei ... rview.html

Here we go with this year's "Google Zeitgeist 2010: How the world searched"
http://www.google.com/intl/en/press/zeitgeist2010/