Autobiographies will become useless in twenty years, perhaps sooner. If every aspect of your life is documented via status updates, tweets, check-ins, pinteresting(?) and such there will be no need for future luminaries to put pen to paper to let a hungry public know how it all happened. But maybe there will be a bigger need for autobiography than ever if we want some actual meaning.
This is where I post the things we've done and you can be all like, "Whoa that's awesome!" and I'll be all like "You're right!" Now watch the movies at 51deep.com or I'll murder you.