Man, I love Ruby. I think it is much more elegant than Python and I really really wish Ruby would have taken the world instead of Python. That said, it's often the case where I want to do something where there's just no Ruby library for it (or at least not a maintained one) and there's a well known library for it in Python. Note: I do low level things, I don't do anything related to web or Rails.

Also, sometimes I start writing scripts for simple things, then they grow and at some point it's interesting to share them to my teammates, and they all immediately dismiss it since it's in Ruby. For that reason, I started doing all my work-related scripting in Python. But oh boy, it's always with that sad feeling of "I wish I was doing this in Ruby". Sometimes I think I should just not have learned Ruby and jumped straight to Python.