So, I have been following Treyarch on Facebook. I don't know if anyone has been either, but if not basically they say that there will be more stuff added in 2017, but that's all they say. Nothing about what it is. Jason Blundell, however, dropped a name of a feature in zombies called Newton's Cookbook. Here's a sourse. Hope it's a good enough sourse.
UPDATE: So Newton's Cookbook can allow you to turn lesser Gobblegums into better ones. Say you have nine Burned Outs. You can use Newton's Cookbook to turn it into one Perkaholic. Just watched a live stream on Youtube with footage of Newton's Cookbook.