There seems to be nobody on the inside counting this. There are no official counts I know about. Re metas however, any editor could count the metas using tools at his disposal - but to reveal the results outside would be against the rules I think.
Re active editors, I see many cases of people counting the number of unique editor names in the RDF (rdf.dmoz.org) dump. But this would still be an exaggeration. So based on some of these (old) estimates, the number active editors is less than 10,000.
You'll be able to find more informtion here:
http://en.wikipedia.org/wiki/Dmoz.org_directory - Right now that info is not in tip-top condition but I imagine in due course, and ferreting around the linked sites, you'll find the information you're interested in.
I don't know why you want to exclude the number of metas for the figures for active editors - they do edit.