Tony and Deana,
can you stop people being allowed to start new posts on the old forum? ... there were quite a few in the last couple of days.
Perhaps you might be able to link to the new one if they try?
Or at least have a very prominent notice and re-direction to this new forum, as the landing page of the old one, before being allowed to proceed to login (and hopefully then to only be able to read or reply to existing posts) for a few weeks?
That will get this new one humming, and let the old one fade away gracefully.