The current wave of new communication and collaboration tools that hit the shore will not kill Email (sunbathing on the beach). In fact, it will only make Email stronger. In addition, only the tools that integrate nicely and purposefully with Email will thrive.
How is that? Well, by introducing new tools which are more suited for the purposes where Email is ill suited, chances are that Email will be used for the things it is good at and not for the other things.
The Akilles heel of Email is that it can be used for any kind of communication. The simplicity and availability of Email encourages people to use it by default when communicating with other people. Email has become the primary choice for people. But if we don't reflect on how we use it and use alternative tools for purposes where email is less suited (which we obviously don't), it quickly leads to inbox hell, occupational spam, information overload...call it whatever you like. Work-related information is mixed with information which is not work-related, private discussions are mixed with official one-way broadcasting, small notifications are mixed with emails containing large attachments, fragments of discussions are fragmented and scattered around in the inbox, information in emails tend to multiply like a virus when you get involved in or start a reply circus act...I think you get the picture.
Above all other things, there are two factors which must stand accountable for these consequences:
1. THE TOOLS
The lack of easy to use and readily available tools that are better suited for uses where Email performs bad (such as collaborating on documents)
The existing attitudes and behavior of people, coupled with the tendencies that people tend to act without thinking and always choose the most convenient solution in sight, not the one which is most suited for the specific purpose.
These two things are what we have to work at to change.
Obviously, this reasoning does not only apply to the Email paradigm, but also to other paradigms as the Document Management paradigm. Why is collaborating on business content still equivalent to putting the content into a container called "document" and shuffling it back and forth?
You already know the answer to that last question; because there have not been any good alternative tools for along time (although now there are) and because it is such a big thing for us to change how we think and behave.
Email is dead. Long live Email.