Facebook Privacy: Check your “Instant Personalization” Setting
The new Facebook privacy setting called “Instant Personalization” is in effect. The new setting shares your data with non-FB sites and may automatically be set to “enabled”.
To check and to change, go to:
Account > Privacy setting > Apps & Websites > Instant Personalization > Edit settings and uncheck “Enable”.
Your friends should do this too, or else they may be sharing information about you as well!