This is really exciting stuff. Mathematica is by far my favorite environment for doing data exploration and mathematics, and although there is a learning curve,

This is really exciting stuff. Mathematica is by far my favorite environment for doing data exploration and mathematics, and although there is a learning curve, the features of the language itself (pattern matching, symbolic manipulation) are extremely powerful. The quality and depth of Mathematica's documentation are excellent, and with these notebook interface changes things are bound to become even easier. Jupyter + tensorflow/scikitlearn comes close nowadays for machine learning, but I love having access to consistent data sets from within the environment.