I'm pretty sure 20 years old and less people really don't care about their timeline privacy and if they do, they can easily change that.
People that "care" about those issues are 25+ tech people, my mom do not care, and teens in my family reallly do not care
the new facebook features prove that facebook is really moving forward in the 'social' space and are succeeding. Google+ a threat? I don't think so, maybe for the old facebook, but not this.. I can already see all new moms going crazy about that timeline feature.
It's boring to see so much articles about how bad 'privacy' is, how creepy facebook is and etc. Seriously anyone can see that.. there is privacy if you look for it, if you don't it simply to assume that you want your profile public..