I came upon this interesting video through a LinkedIn contact. It seems that with internet, social media and now having access to all of it in your pocket (smartphone) have lead to the decrease of the attention span from 20 minutes to 9 seconds (that a two order of magnitude decrease – a 133 to be more precise!).
You Only Get 9 Seconds » Sally Hogshead, Keynote Speaker – YouTube
Next time you sit in a meeting or are in a classroom, you might want to do a little experiment and see how often people divert their attention to their phones.