Lots of differences. node.js is an async development framework. Tornado is a synchronous development framework that is slowly building up asynchronous alternatives where the need is great enough until it eventually becomes twisted or people just deal with the things they can't do.
node.js is asynchronous from the ground up, Tornado is generally synchronous with the exception of http client and server. So, Tornado is less pure, but you can use any of the Python libraries as they are. Node.js is pure, even disk i/o is asynchronous, but there are much fewer libraries.
Tornado also wraps Facebook API and has authentication with Facebook, Google, Twitter and everyone else.