Switched from Django to Tornado a few month ago, and I've never looked back since. In Tornado everything just seems to makes sense and nothing gets in your way. I've worked with Django for couple years and never felt this way.
It's not the non-blocking part that pulled me in, but simple APIs that make sense. In Django, I always feel that I'm spending my precious time to learn "the Django way", in Tornado, once you learn the few basic things, you can focus on doing things.
It's also wonderful that Tornado's codebase is still compact enough that you can easily understand and modify it, if it doesn't provide the functionality you need.
It's not the non-blocking part that pulled me in, but simple APIs that make sense. In Django, I always feel that I'm spending my precious time to learn "the Django way", in Tornado, once you learn the few basic things, you can focus on doing things.
It's also wonderful that Tornado's codebase is still compact enough that you can easily understand and modify it, if it doesn't provide the functionality you need.