Osso, you can have different privacy setting for people and pictures.
You can set up family groups, friends, acquaintances and work groups. Each of these groups can have different privileges on what info you wish to share with them. You can set who reads your wall, or messages etc.
Your pictures and albums can also be set to different settings, they can be viewed by no one to everybody, depending on what you choose.
As for this ad campaign, if you were to do it five times in a row, it would have a different choice of people each time. It`s frustrating because privacy laws are different in each country. I rarely use or respond to any group or app on facebook now, but I do find it very handy to send quick notes, photos and keep up with friends.