Email isn’t just for direct communication but it can be used for notifications, too. I can put up a blog post or two and then send a brief email message to a list of friends and family with the links. This ia actually a method of using sender-stored email where the blog post becomes the sender-stored message and the notification is via the email notice.
Beyond notifications, it’s a way to stay in touch with an exact set of family and friends which is otherwise hard to do. That’s because some are on Facebook, some on Twitter, maybe even on Google+? Nah, probably not Google+. Who knows, but I think email is still universal.