Google has no interests or demographics for me and I do not go nearly as far as this article suggests. I use adblock, wallflower, and antisocial extensions, as well as the do not track feature of firefox. But I am constantly signed in to gmail, frequently in amazon, and other places. Use firefox for all my browsing and don't really worry about it. If anyone wants to get information on me I am sure there are many more ways to get it than google anyway. While I like my privacy I have to accept that in this day and age it is relatively easy to find information about someone.