As I commented in another post bashing email recently, there's nothing to fix, and this can be easily pushed to the client. As a messaging protocol, email works great. If you want JSON messaging included, you could build a client that reads that specific MIME type and interprets it differently than other messages. Is this not how Outlook meeting requests work? They are just shown as random attachments in non-supporting clients. Outlook meetings are not part of the email standard, nor should they be.

We don't need to add more cruft to email itself. If you want to create extra protocols for doing different things using email as a medium, go ahead. Email is extendable, as Microsoft, Gmail, Xobni, etc have shown.

Long story short, you can do whatever the hell you want with email. It's not perfect, but it's a really great messaging framework. You can send any message you like, to whomever you like. How the recipient interprets that message is up to them (ie their client).

EDIT: just wrote this up since I'm sick of repeating myself: http://blog.killtheradio.net/technology/email-is-not-broken-...