IBM Watson learns a topic very quickly.
Experts I spoke with said that when provided with access to adequate written material, IBM Watson can answers questions as accurately as an expert in the field 60% of the time. When an expert coaches IBM Watson for 8 weeks on a topic, IBM Watson can answers questions as accurately as an expert in the field 90% of the time.
You don't program Watson. You teach it
There is no programming language for IBM Watson. Product managers and domain experts can simple teach Watson by providing written material and training it.
I think there are interesting possibilities with Watson in the areas of education and healthcare.