There's less friction in moving to a new email provider. You sign up, you blast your contacts "Hey folks, got a new email address", and you're off to the races

There's less friction in moving to a new email provider. You sign up, you blast your contacts "Hey folks, got a new email address", and you're off to the races. Social networks have circles, permissions, and all sorts of other clinginess. Additionally, there are features in email that you won't expect from these nodes like a useful (to muggles) data export. I can pull down my email with IMAP or POP, close that account, and still have access to all of my old email. Hell, I could _reply_ to one of those old conversations using my new account/provider and keep right on trucking.