[atrudeau]

From a practical point of view, I'd agree with others: you're only missing a checked box on your resume.

From a non-practical point of view, you're missing out on the pure joy of writing Ruby. Everyone should try it at least a couple of times to see just how expressive and fun programming can be. As someone who programs regularly in Python, Go, JavaScript, and Java, Ruby blows them away in FUN points.

As a side note, it would be awesome if someone wrote a Ruby -> Python compiler. I would love to be able to call NumPy from Ruby code. I would even be happy with a (generous) subset of the language. I think gluing together Python libs with Ruby would be a pleasure, and people could start using DSL magic to implement better APIs for existing libraries.