SwarmESB have a new and simple programming model. With swarms I'm hoping to make ESBs mainstream to normal programmers.
An ESB is a big and complex project and you can contribute in many ways: code new features, examples, documentation, tests.
We need collaborators native English speakers, capable to create real hype around swarms by writing nice articles, showing proof of concepts. Also, we are open for collaboration with academic researchers to publish new articles on swarms!
For really good programmers, with passion on distributed systems new implementation for bus communication (now based on Redis pub/sub) or mechanisms for fail recovery,etc.