Previously, when you first joined Facebook, all of your posts would be shared with the world by default. Anyone who stumbled upon your profile could read anything you previously shared, be it a short update or a personal photo, unless you deliberately clicked away from "Public." Now, the social site's switched things up for the better, making "Friends" the new default for status updates. You don't have to do anything to take advantage, but now's as good a time as any to pay very close attention to your Facebook privacy settings. And maybe be a bit more selective when it comes time to add a new friend.