First it's important to note that the importance of programming languages is time sensitive, it depends of current programming language maturity and their related tools: VB was a success mainly because the IDE gave a lot of power to [below] average developers.
In my opinion:
i) C#: It's the most advanced general purpose programming language. ii) Python: Excelent scripting and glue. iii) Javascript: It's the Web!
But for system programming...: i) Assembler ii) C++ iii) Python. It's good for Reverse Engineering too!