As a general statement I would never recommend someone to not learn a language. Currently Python has a strong position in some areas of the scientific community, and loits of libraries and tools are available. Python also have a history so that old projects and coders are more likely to use it.
Julia is a young language with new ways of expressing problems that we keep on refining. In my opinion, the most important features in Julia is multiple dispatch and a very nice type system. Method overloading makes it easy to express generic algorithms. If a Julia program performs badly, it is usually fairly easy to code around some known rough edges and achieve runtime speeds about 2 times of a similar program written in C.
