CiviMail Social Media Media Integration
Okay, I'll bite, I've got a client with the same request and I'll bet lots of people would use it if it was there.

The post you reference has some code for how to create a token that can be used in manually building some html to include in your email, which in theory is all your really need.

What would be nice is:
1. A series of tokens for each of the different social media share options to simplify the civimail editor's job.
2. A test by those tokens that would hide the share links on emails that aren't configured for public archiving.

Sounds like a simple extension. Or what was your experience?

As an aside, here's what a CiviCRM competitor is offering: https://blog.aweber.com/email-marketing/social-share-buttons-in-your-emails.htm