I agree that this convention is useful.
We have dozens of Node projects at my office, and you can tell the age of them by whether the start script is "grunt", "gulp", "npm run dev" or "npm start".
Using [per-env][0], we've begun replacing all setup and all starts for every environment to be "npm install" and "npm start".
[0]: https://github.com/ericclemmons/per-env
