I don't think anybody types "porn" when looking for porn.. I could probably join on three more terms and exceed facebook: http://tr.im/dvoc.
Just a thought -- you get what you measure.
Just a thought -- you get what you measure.
On a side note, what really boggles the mind is the number of searches for "google" or "google.com". According to the Keyword Tool, there were approximately 30mil exact searches for "google", and 7.4mil searches for "google.com"!