No lipsync of facial animation, but...
Since the animator is decoupled from the sprite itself, it can now animate a proxy object which doesn't do anything - but internally creating a bunch of hidden sprite children which don't get deleted - only one is enabled at a time. Sounds a bit crazy, but it gives you one big advantage - the cost of changing frames costs a lot less with this, and you can also have complex colliders (polygon colliders too!) animating. Its not something you want to use every time, but there are times this could be invaluable.
Another use - since the animator can also link up and play variants of the same animation in sync, so you can say Play("walk") and you can have all bodyparts animating correctly without having to sync everything up by hand.