We just fixed this--sorry we didn't have it to start out with!

If you go to your profile you'll now see a checkbox in the 'icon' section that says "Use Facebook image"--uncheck that if you don't want us to use your Facebook image (you'll only see that checkbox if you've connected your Facebook account).

As a rule, we can only access Facebook information that you've authorized through Facebook itself. By default, this is your name and photo--but you have full control over that in Facebook.