I think this is one option that is to be discussed. However, there is some similarity. At least mediators are executed by a receiver after the modules have acted.
One thing that came up on the IRC is that mediators are services. I didn' realize at the time, but looking at the prototype code that was meant literally wasn't it? A mediator is an AXIS2 service, with ServiceDescription, ServiceContext etc. And further, mediators are in one ServiceGroup?
Is this really the intention, and having a single Synapse service as refered to by step 3 in both option 1 and 2 on the wiki has changed?