Currently we’ve whitelisted 2935 domains, out of more than 95238 in the current beta signup list (number from 24 Oct). While admittedly that’s only 3%, it’s an interesting game to see how many of those invitations turn into certificate issuances - as you pointed out, there are so far only 203 certificates issued. We’ll be doubling that number of whitelisted domains tomorrow.
Whitelist updates take a certain amount of paperwork as part of our Webtrust obligations, so it’s batched and not an automated every hour kind of beta like we’d prefer. Of course, while anything can be automated – even the paperwork – given that GA is only a few weeks away, manual paperwork for this seems OK for now.