The product manager for Google Plus just punched a hole in his hat.

On a serious note, there were platforms that used to dominate discourse on the internet before Facebook. Usenet, ICQ, AOL, Myspace.

Now there are alternatives. Medium for blogging; Reddit and 4chan for discussion; Twitter for sharing breaking news, trolling celebrities, and complaining about customer service; LinkedIn for connections and keeping in touch; Pinterest for sharing photos and links; Snapchat for sharing photos and videos; et cetera. I have a few friends, particularly in the 25-and-below generation, who don't have a Facebook but are very active on Snapchat or when it was trendy, Vine.

Don't forget countries where Facebook is a minority player. Weibo, Renren, WeChat, VKontakte are examples of thriving social networks that could possibly grow beyond their borders.

social networks are a natural monopoly, you want everybody to be on the same one. So if you want to avoid the centralized authority problem, you need to define it as a network of many nodes communicating via open protocols. Sort of like email. This is how Diaspora and GNU Social work.

They exist. But they need love.

Diaspora is nice.