So, applying Taleb’s reasoning and Benoit Mandelbrot’s version of the Lindy effect, our modern social technologies — most of which haven’t been with us more than five years — can be guaranteed to be with us only an addition five years or so. And those pre- or proto-social technologies — like instant messaging and email — may be with us 50 years or more, even if the social tools don’t fall into disuse.

So, if you are scratching your head five or ten years from now, and wondering why people are still using email to do things that might be better done with newer and shinier tools, just remember this is not about rationality, it’s about something more like gravity, more like deep culture:

If there’s something in the culture – say, a practice or a religion that you don’t understand – yet has been done for a long time – don’t call it “irrational.” And: Don’t expect the practice to discontinue.

via Why we will be using email for at least another 50 years — GigaOM Pro.