First, it's not social vs email. Email was the first social network -- anytime two people interact (regardless of the channel) it's a social interaction. Those who claim email is dying have an agenda to promote other solutions.
If email is dying then why is that you can't sign up for FB or Facebook or any other social network without having an email address? Why is it that FB started their own email service? Why is it that FB and Twitter and all the other networks send out billions of emails each year? Witout email as an aquisition and retention channel, networks such as FB and LinkedIn and others wouldn't even exist. The entire debate about email dying is a red herring and always has been.
Let me know when another channel can return $40 for evey $1 dollar invested in it and then I'll be impressed
I hope this helps.