The problem with Twitter alternatives is that they only see adoption from the type of people who seek out Twitter alternatives.

The current backlash against surveillance may change that - or so I hope...

GNUSocial (eg Quitter.se) and Pumpio (eg Identi.ca*) are functional replacements with thriving communities.

Those are too social network orientated for what I wanted. I appreciate they do model themselves after Twitter, but for me the appeal of Twitter is that it can also be read anonymously - like a pretty RSS feed or Growl service - if that's all you want to take away from it.

With GNU social (founder here) you can do that too.

You can even subscribe to people on Twitter, post to Twitter and still get ATOM, RSS and FoaF out on your end.

See https://mattl.io/replies for a more traditional view.

Thank you. I'll give that a try the next time I have time to tinker. :)

I think identi.ca is one of the more important ones (which doesn't say much, I tried to figure out that ecosystem a while back and found it pretty hard to get into for outsiders)

Apart from https://gnu.io/social/ and http://pump.io/ which have already been mentioned, I have a soft spot for https://project.jappix.com/features and https://movim.eu/en because of their use of XMPP pubsub which I believe to be the ideal infrastructure for decentralized microblogging. But for lack of large entities pouring tides of promotion money into them, they all have small populations.