Tent really really needs some justification docs.
There are also a few projects using XMPP, like BuddyCloud, Jappix, Movim, OneSocialWeb etc.
I find that all of the open social initiatives are either too broad or too specific. OStatus is entirely too broad, from their FAQ:
> First, rather than being a stand-alone spec it builds upon several existing (and evolving) open web standards including: PubSubHubbub, Webfinger, ActivityStreams and Salmon.
So if I'm a developer I can't just learn OStatus, I have to learn 4 other specs as well. Diaspora has the opposite problem, it's too specific. Their recommendation for contributions is to fork their rails app. Developers don't want to fork working apps and fix bugs; they want to write their own from scratch.
Spot on.
And as all of the protocols necessary already exist and are quite well-established, there are already parsing tools available for anyone to use freely. So development is really easy to get into when it comes to OStatus.
Using something that already exists is in this case much better than reinventing the wheel and rediscovering all implementation issues that have already been taken care of with protocols like XMPP or OStatus.