Quickly: Node is great if you have a JS heavy team, and want to have one language to rule them all... and potentially share logic using something like Browseri

Quickly: Node is great if you have a JS heavy team, and want to have one language to rule them all... and potentially share logic using something like Browserify. In our experience on Vidpresso, we started out with a Node app... however for the core app we found that Rails' productivity gains outweighed Node's sharing of logic, etc. With a bootstrapped team, Rails' maturity just made Node seem like not a good idea. (Django would be fine too, but one of our core guys has done rails forevs.) We still use Node as a critical part of infrastructure, but now it's relegated to message bus / socket.io-ey stuff. (Talks with rails via redis pubsub.) So yes, you can totally do your entire stack on Node... but you have to make a lot of decisions. If you're someone like TJ (the guy behind express) and you're comfortable making lots of decisions yourself, it's extremely great. FWIW for Node noobs, Express is just like Sinatra. There are higher level frameworks, but none that has really 'run the table' like Rails or Django.