I don't see email disappearing. It is one of the classes of communication, from least disruptive to most disruptive:
Messaging - email, fb, linkedin, etc
Broadcasting - twitter, fb wall, rss, etc
Instant Messaging - skype, irc, etc
Calling - skype, phone, etc
In Person
That people are doing more messaging through fb, linkedin etc doesn't change that what they are doing is essentially email.
Messaging - email, fb, linkedin, etc
Broadcasting - twitter, fb wall, rss, etc
Instant Messaging - skype, irc, etc
Calling - skype, phone, etc
In Person
That people are doing more messaging through fb, linkedin etc doesn't change that what they are doing is essentially email.