For a new project I'd like to use an Open Source ESB (Mule, OpenESB, ServiceMix etc) deployed to a cloud infrastructure (Google App Engine, Heroku, Amazon).
Are there any good resources on this and in particular issues such as scalability, state replication between cloud instances etc? I couldn't find very much on this topic!
I'm aware that Mule has its own cloud offering (Mule iON) - but I don't think this is exactly what I am looking for.
Many thanks,
Ken