I'd say that behavioural economics is the field that has made the greatest progress over the past one/two decades (though it pains me profoundly to say so because it's the furthest removed from my area of the discipline).
Honestly, from my perspective (trained as a psychologist), behavioural economics is essentially running social psychology experiments on economic behvaiour.
While it's great that economists have finally abandoned rational actors, it's not really news to the rest of the social science world.
