Take Twentyfive: On Body Language
One of the few things that make or break a good animation is good body language. It is reading between the lines, "body leaking", secondary actions...
It is all about what the body is saying and not what the mouth is on about.
You have heard of Smiling that engages the eyes (true smile) and Smiling that does not effect the eyes (fake smile).
Animation is about observing human behaviour and translating it into believable motion, motion that speaks to our instincts and not just the images our eyes perceive.
Every now and then I stumble on pictures that are just so telling of that specific situation, the feelings within, the people behind the motions and as a special treat, the face is not even shown:
Do the hands talk to you? Do both of them tell you so so so much about each person behind that kiss? Do you love it or do you love it?!