Email doesn't need replacing. For insecure iterated text communication, it's just fine. Oh we might quibble about the restrictions it places on us as programmer

Email doesn't need replacing. For insecure iterated text communication, it's just fine. Oh we might quibble about the restrictions it places on us as programmers, but it works from an end user perspective pretty much 'okay.' However, a lot of communication is not insecure iterated text communication. Email's not so much broken as it is incomplete and largely inextensible. From that perspective, even something as simple as having a chat with someone through email seems very odd. I mean why are our replies to each other different messages? Why aren't they just inserted seamlessly into one thread in the same way that IRC works? Setting up a meeting? Oh I know that there are email setups that can do that in corp-space, and theoretically a civ-space client could use them too. But that's not the way things tend to go. In many ways the use of social media to setup meetings is the direct result of emails lack of extensibility in this regard. Keeping group photo albums? Should be easily doable without the need for a central server like facebook. Secure chat? Oh, where will we get a trusted certificate authority from? Well, if you don't want to meet the person you've got that problem whatever you'd doing. If you can see the other person, however, you just generate a short random string on your computer, encode it with their public key and see whether they can decode it at their end. No point exchanging the whole key, just check the thing works. Varying access levels by trust? Keeping a persistent contacts list across multiple devices? Presence-aware communication? (Actually knowing someone's at the other end and available right then.) So people, to varying extents, use other tools for these things. The major cheerleader for email's borked at the moment seems to be the security aspect, with implications for trusted senders. I mean heck, that's something that would kill most spam right away there - if you had senders that were verifiable as the same person every time, you could implement something like: 'X wants to send to add you to their contact book, do you know them?' Public-facing email addresses would still get spam but we could just blacklist everyone you said you didn't know for your private address and not bother decoding the messages at all - straight to the bin with them.