Jami protocols, please
I am now using Jami, but it's not perfect yet. I am not sure Jami is yet easy-use and easy-maintenance enough for me to ask some of my friends to install it, though I hope it will get there. I also, oddly, feel that it is too centralized!
In order to use Jami, I had to add the Savoir-faire repository, and download the latest version directly from there. All my friends will have to do the same to keep their versions in sync.
In some ways, this is more centralized than Mumble, which is not peer-to-peer, but has multiple third-party applications for both server and client (Mumble also has no end-to-end encryption; the server operator is a de-facto party to all group calls, so you have to run your own server).
A Jami protocol would fix, allowing different versions and implementations to interoperate. It's hard to write a protocol without first writing a prototype implementation. I very much hope that Jami will, like Mediagoblin, eventually spawn a protocol.
Then Jami will be like a peer-to-peer Mumble; we can use different versions, and if a Jami becomes not quite what we want we can seamlessly switch to another program, keeping our contact list and histories. Free as in freedom.
A protocol just for account data storage/import/export would be a good first step; a protocol for the actual messages could come later.