Hi,
Sorry for the slow response. To answer Dave and Sean's question: I'm not 100% sure, now having dug into it, how to get involved. On the plus side: All the work that the IIS group developed is housed at CEDS. So I think getting involved with CEDS is the right place.
*However* CEDS is in between contracts (from version 4 to to 5 I think). So there's no actual working group to work with right now!
Joe Hobson from NavNorth is going to post some suggested subject taxonomy vocabularies soon to continue to expand this work, so that should be helpful.
My best suggestion, unfortunately, is to keep an eye on the status of CEDS working groups and get involved in those. I will be working to try to find a better answer than that in the meantime. Feedback and public or private communication welcome on this as always..
Steve