We've considered it, in some capacity. Generally the results are often not very good, though sometimes they can be and AI is progressing rapidly.
Animators are an interesting breed. Consider these are people who used to draw 12 or more complete frames per second. They tend to be very detail oriented and want full control over how the animation looks. AI or other automation can still be useful, but this should be taken into consideration.
I think physics will be more immediately useful. Physics is a way of having a good deal of animation done for you, usually the tedious secondary motion. It also adds dynamics, as movements of physics influenced parts of the skeleton will often vary each time an animation is played.