What changed
Skinning lets you take leather from certain creatures. In Classic WoW the corpse disappeared after the first skinning. During the past two weeks of the Forever beta, however, grouped players could skin a creature several times, once per group member, so a single mob yielded much more leather.
For a long time it was unclear whether that was intended.
Effect on the economy
The latest build makes clear that this was a bug. Only one player may skin each creature again. That affects the leather economy when Forever launches on 4 November, because supply will be lower than the recent beta suggested.
Original report: Wowhead