Google's Yu Chen has posted info about how see you can view your trended Google search data:
"To use it, you have to turn on Personalized Search and be signed in to your Google Account while you search. (If you don't have a Google Account, it's easy to create one for free.) Just click the "Trends" link on your Search History page, or go directly to your Trends."
A lot of data. Here's my view:
Monthly and daily search activity: