Within the My settings area the email field is required for the "I forgot my password" function. If you lose your username or password the login details will be re-sent to you via this function.
In addition to the above function the email is also used within our community portal as an identifyer for your portal account.
Note: You can always change your password by clicking the green "Change Password" button. The username is a unique indicator in the Publicator system that cannot be changed.