The problem is: plain Julia is faster than plain CPython. But Numba has solved this problem for me, by compiling my hot loop in-place. Other people report similar success with PyPy, Cython, or Pyston.

Furthermore, libraries like scikit-learn, pandas, matplotlib, or scipy are incredibly powerful, and usually implement in fast languages. Python is only there to glue them together.

For my applications, I just don't see any compelling reason why I should use Julia over Python. In practice, Julia is (for the above reasons) not faster in practice, and the libraries are a lot less mature. I try Julia every few months though, and there is progress. Maybe in a few years.