A couple of recent news items have got us thinking about the future of e-mail. First, Google announced that its Google Wave service was officially out of beta testing, meaning they’re done with the development of it, it’s a full-fledged thing. But Wave has been anything but a success since its launch last year. What was supposedly the evolution of email has been an interesting experiment without very widespread adoption. And while Wave stumbled, e-mail just keeps trucking along.

Second item: last week Facebook COO Sheryl Sandberg gave a speech where she predicted that e-mail was on the way out, to be replaced by instant messaging, texting, and messages through social media. She cited a study by the Pew Internet and American Life Project that said only 11% of American teenagers use e-mail on a daily basis.

We speak to that study’s author, Amanda Lenhart, who puts those numbers in context. We also check in with market researcher Sara Radicati who tells us that e-mail is actually growing.