Special privacy considerations
You have one profile across all Google services. This means your personal data, searches and behavior are available to all Google applications and advertising. You should log out and use private browsing for Google services that you do not want associated with your Google profile.
Concentration of data increases privacy risk. Google’s privacy score does not reflect the additional risk posed by the breadth of Google’s data collection. If you make extensive Google services – such as Google Search and Gmail -- this increases the impact on your privacy if Google does not honor its privacy policies.
New privacy policy. This privacyscore is based on Google's revised and unified privacy policy, which will be effective on March 1, 2012.