I spent the last 2 months building an app on rails and I've really enjoyed it. The available plugins and docs are great. With a bit more of a python background, I've really enjoyed Ruby. The ruby way of doing things seems more intuitive to me now, and I struggle a little bit when programming in python (not much, but I feel pythons stricter syntax and grammar to be a little bit of friction)

Someone else here compared ruby to python. They said ruby is quicker and smoother for UI programming, python is faster and better developed for computation. I think that answer is dead on.