My main question is how to support both direct and indirect (via a "social" client (as if email wasn't social)) usage in a sustainable fashion. Otherwise I don't see it gaining traction.
I'm not sure how much of a chance it would have of succeeding (I'd like it, but would anyone else?). One thing that gives me a bit of hope is the rising popularity recently of email newsletters on specific topics or from specific writers/thought-leaders.
It may, because it doesn't have to build it's own network effect, it can piggyback on emails existing userbase, which is basically everyone.
I was talking with my housemate, we came up with the idea of a combination push and pull following mechanism. I can offer you the option to follow me by sending you a mail with the X-SOCIAL header and a "follow offer" header content, plus a really simple mail body that says "hey, substance just asked you to join their social updates list. it seems you don't have a social client, <click here> to get one". If you've got a social client installed already, the body gets hidden and you get the follow offer in your social client.
However, you could also send me a mail with the X-SOCIAL "follow request" header, and a similar introductory body: "Hey, skewart wants to keep in touch with you via social mail. Download a social client <here> to connect with them". If I have a social client installed, I get a friend request instead.
The great thing is, your email inbox has a timestamped record of all these requests, so it's like a somewhat unreliable replayable social history, which means if I don't have a social client, I can read the introductory body, go grab a social client and come back, and it will re-parse my inbox and offer me the same follow request, no need for you to resend it.
God damn it, now I like this idea.
Man, now I want to build this thing.
On the receiver or "follower" side of things the client would filter emails coming from addresses you follow into a separate social feed box. All your other emails (e.g. from other random people, or the notification that the shoes you just bought online have been shipped) would be displayed in your standard, traditional inbox. Your list of actual, non-social-update emails would never be polluted by all the noise from your social update feed.
On the sender or "poster" side of things when you post something it would just send emails to your list of followers. Presumably all these people are using clients that are designed to filter the emails into either the social feed or the standard inbox. So you'd never end up spamming people with photos of your lunch on a Greek island with people who haven't signed up to see it.
Of course, it could get tricky if, say, [email protected] is following [email protected] and bob wants to send alice a plain old email that isn't part of his social feed. Using headers, as suggested above, could be great. Or maybe the social feed would be set up as a mailing list, and posts would go through a reflector address. Or else, maybe people would just set up a new email address from which to send posts to their network?
Or, maybe I'm misunderstanding your question?
I dunno. I haven't thought through everything, but I'm pretty confident that existing email infrastructure has all the raw material you'd need to build a workable social network.