I suspect the average teenager today hardly uses e-mail at all.
Yes -- I was surprised (and somewhat weirded out) recently to discover that my younger sister, who's in her early twenties, thinks of email exclusively as a formal communications channel, and never emails her friends (she texts or Facebook-messages them instead).
I'd never heard it in quite those terms before, but that echoes the way that my generation might consider e-mail to be for talking to friends and physical letters to be "formal".
Yes -- I was surprised (and somewhat weirded out) recently to discover that my younger sister, who's in her early twenties, thinks of email exclusively as a formal communications channel, and never emails her friends (she texts or Facebook-messages them instead).