Facebook sustainability I believe, lies with keeping those from age 13 upward engaged. Charlene Li perhaps underestimates the scope of said youth demographic. From personal experience my 14 year old daughter has been active on Facebook for at least the past two years, and I doubt she has a schoolmate, or neighborhood children, who I have not seen there. "They're not interested", claims Li? I too used to tell my parents almost anything I thought they wanted to hear (read: dumb enough to believe). Thinking back, and it hasn't changed, the reality was, and is, vastly different. Parents know a lot more, but seldom 'get' where their kids are until, it's become a 'got', and they're just 'so over it'. From what I see, RE Kids and Facebook, they are already inextricably linked, not just on Fb, but everywhere, and therein lies the difference, that will not change significantly, while we parents still have the wherewithal to watch.