To be honest it's not something they need to really make a topic on. The last time they made an animation topic was to show the scaling of everything since the animations already exist, they just replaced it temporarily.

Though the question is, whether they meant implementation between 1.21 - 2.0 or rather internal working starting after 1.21 launch (basically like how they're working on new servers and server tools that won't be put into play for version 1.x.)