re: "to focus on internal networks...."

what sort of features do you have in mind which would "justify" a fork rather than a PlugIn to extend functionality ?

We are considering two different forks of Elgg - based on (1) our own heavy customizing of the Elgg Core and (2) based on "Distributed Elgg: Theoretical Design Concept" presented at ElggCamp 2009 at Harvard University Boston,

We have not formalized any particular logistics, just simply toying with the idea thru our synapses.. for now.