Also, kids don't like social networks where their parents hang out. This more than anything else will kill Facebook -- it'll be what old people do. Of course,

Also, kids don't like social networks where their parents hang out. This more than anything else will kill Facebook -- it'll be what old people do. Of course, Facebook could acquire (and Messenger and Whatsapp and Instagram are powerful moats) but the core social network functionality is weaker than it appears.