I've updated the wiki a bit, added some links to the JIRA, attached the UML diagram, etc.
As a comment - could we replace the ZIP archive with a patch file? Easier to view diffs, etc.
Should also discuss how the old Interceptor.invoke(InvocationContext ctx) interface is dealt with, since custom interceptors will extend Interceptor.
Ok I had a think about the Commands being immutable, at least by the Interceptors - won't work. There are some Interceptors that change the parameters of the call, such as the MarshalledValueInterceptor that wraps and unwraps payloads as MarshalledValues.