Good thread Harry. I don't tweet or face book because I am concerned about the level of personal info that is up for public knowledge, and also because I couldn't care less what everyone else is doing. There is one other aspect of what the video implies. If you are posting photos that have GPS coordinates that are hundreds or thousands of kilometers away from your home address that means you aren't at home.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.