How easy it's now going to be to increase their numbers.
Have your Bible study attend the occasional meeting, ask them if they've been speaking to others about it or anything spiritual and they are instantly an active publisher.
JW children won't need to be going door knocking, likely all they will need is the nod of an Elder who hears about their informal witnessing and they too can be actively reporting.
It will be interesting to see what the guidelines are but we saw how they changed what they now consider to be a Bible study. I think they can count a return visit who they spend more than 15 minutes at the door with and that person doesn't even know that they are a Bible study.