Yeah I wouldn't call it social in the 'growth hacking' sense... but it's certainly social in that it comes up in conversation nearly as often as Facebook or Twitter (in my non-tech circles).
It's been around since the 1990s, so it's not "sexy".
Even though Amazon has been an important part of my own business for actually selling stuff, Amazon Prime has revolutionised the ability for small sellers to move volume (and solved the logistics hurdles), and Amazon's cloud computing is critical for tons of other startups to run their infrastructure--not to mention is being chosen by established players.
