Nonpartisan Social Network - Continued (Idea)
To avoid appearing too complicated, you would want to market each plugin separately. That is to say, don’t say “An RDF-triple store” that allows FOAF and other plugins. Instead, say a FOAF server, and then, a SIOC server (etc). The reality is that each would be a prepackaged RDF server with a plugin, and on the developer site you could find out more about that (and build a custom multi-plugin server).
The reason for this is - there are far too many solutions that claim to be silver bullets and end up confusing and complicating things. For that reason, users (and developers) may steer clear of things claiming to do too much. I do believe that there is something to be gained through abstraction here, but don’t want to scare people away. For that reason, marketing this as separate servers may work very well.