That stat does not convince me that users actually know what they're doing. Maybe you're privy to more research about this, but I suspect the majority of users who select something besides the default change everything to 'old setting' because they don't know what the hell this stuff is and just want to get back to Farmville.

I seriously doubt most people know what 'Everyone' means. Or what can happen to data that's syndicated to search engines and is no longer in Facebook's control.

I'm currently in the process of reaching out to my friends who don't follow tech news to make sure they know what they've signed up for with the new settings. After explaining the 'Everyone' setting, responses are usually along the lines of "Facebook is turning evil."