I know Python well but don't know Ruby. I'd like to start building serious Web apps and would love to hear why you like RoR more than any of the Python frameworks. I am under the impression that though there are more people who know Python than Ruby, yet more Web dev is done with RoR than all of Python combined, and I'm curious why. What is it that is so attractive about Rails? And with Rails having been the #1 reason for people to learn Ruby for years now, why is there no parallel Python on Rails?