According to CHART OF THE DAY: Email’s Reign Is Over, Social Networking Is The New King. The proof is here:
Now, alot of people use platforms like Facebook for email and instant messaging, essentially transferring what they do with sites and tools like Hotmail and MSN to Facebook. But they are also do more than that, and that’s likely one of the reason social networking is winning out for the time being.
Smart People I Know 