Re: What's the latest in the MQ scene? AMQP 1.0 and RestMQ are dead on arrival? XMPP is too complex. IRC is old. ZeroMQ is too little.
What's your checklist for an MQ server?
I'm working on a simple one in node.js to serve as a reliable relay among portable, intermittently online devices. Its protocol is based on websockets, but without the HTTP handshake, and message headers are JSON with a size prefix.
It allows large binary messages, short messages to user aliases (anti-spam measure), multiple clients per user, multiple recipients per message, distribution lists. It doesn't federate, but I plan to add an email gateway to it. It's supposed to be reliable, so it does fsync() before acking to a sender, thus storage constrains throughput.
It's only a prototype at this point, using the filesystem for storage, and documentation is minimal.