Rails was designed to provide an opinionated way to solve common web application problems. Node has many of the same capabilities, and a couple frameworks have sprung up to apply the same patterns. Here's what I've missed from rails that I hope to find in a Node framework.
- agreed (“opinionated”) file structure
- conventions for file names
- data migrations (code files that make db schema changes)
- built in auto-compile for Coffeescript SASS/Stylus/LESS and HAML (no need to grunt)
- asset pipeline - versioning of JS and CSS resources, spriting images
- ORM (ActiveRecord): same/similar semantics for MySQL, Postgres, or MongoDB
- Capistrano (or other scripted deploy)
The good news is, with node...
- Plenty of node packages to replace gems
- Unit tests easy enough
- Preparing your app for a PAAS provider (like heroku) enforces good code hygene (environment variables)