What's the Secret Sauce in Ruby on Rails? links to Crossing borders: What's the secret sauce in Ruby on Rails? "Debates about Rails in the Java community have been intense and show no sign of dying down any time soon. Rails proponents boast of incredible productivity, with some claims of 10 to 1 over Java development. As a Java programmer, your knee-jerk response is to dismiss any wild productivity claims because you've likely heard them before and been disappointed. Java advocates increasingly insist that Ruby on Rails is a toy that can't scale, produces bad code, and won't work beyond the simplest applications. But as Rails praise keeps popping up -- often from credible sources -- a more prudent course might be to understand what Rails does well and to bring those ideas back to the Java platform. In this article, I'll explore the core features -- the secret sauce -- that are the essence of Rails's great productivity."
If Ruby is up to 10 times more productive that makes it about as productive as Python, Tcl and Perl, see "An Empirical Comparison of Seven Programming Languages".