Your life can be an open book on Facebook if you want it to, but the problem for some less savvy users is that it's an open book even they don't want it to be. After all, it's not just experienced PC users posting to Facebook anymore -- anyone and just about everyone users the social network these days, and to make sure people aren't sharing more about themselves than they're comfortable with, Facebook is making some changes to its privacy settings.From now on, when someone joins Facebook, the default audience for their posts will be set to Friends only. Prior to the change, the default setting was Public, meaning everything posted could be viewed by anyone on the web. Going forward, only accepted Friends of new users will be able to see their posts. First time posters will also see a reminder to choose an audience, so they can override the default setting from the get-go, or anytime thereafter."While some people want to post to everyone, others have told us that they are more comfortable sharing with a smaller group, like just their friends. We recognize that it is much worse for someone to accidentally share with everyone when they actually meant to share just with friends, compared with the reverse," Facebook explained in a blog post.What if you're already using Facebook? Over the next few weeks, Facebook will roll out a new and expanded privacy checkup tool to all members. This tool will analyze your settings and let you know who you're posting to, which apps you're using, and the privacy of key pieces of information on your profile.In addition to all that, people who have their profile set to Public will see a quick reminder about their setting and ask them if they want to keep it or change it.