If you look in your Personalized Search History Google will tell you how many searches you've done since they started counting. It's been open for 212 days, so divide your searches by that (use google calculator if you don't have one handy, this will also increment it by 1 =). Google says i've done 8177 searches which comes out to just under 40 searches a day.

Should I take a Google Break...? =)

Mine's only about four a day, but I generally use Google UK and that wasn't included in Search History until recently.

BTW, some more people have been discussing this here: http://blogoscoped.com/forum/12868.html