I think that's because Tornado is fantastically simple, and Twisted just isn't. Tornado is the bare-bones essentials for an async web application server. Twist

I think that's because Tornado is fantastically simple, and Twisted just isn't. Tornado is the bare-bones essentials for an async web application server. Twisted is not. You can start with Tornado, then put Django or Twisted on top, but that's optional. Besides, people are kind of scared of Twisted.