1. Tests are essential in any project using a dynamic language; but don't write regular unit tests. Instead write a setup script. A script that sets up basic data in the store by calling various APIs. For example, setup your test users POSTing to /users. Whenever you need to go back to a clean database (which is, often) you can run this script. And of course, every time you want to test all the APIs.
2. Automate everything in scripts. Script your compile, test and deploy steps. Script emailing. Script your database backups, tar your image folders.
3. Refactor every time you get a chance. It is like having a bath. You feel like working on your app, code feels fresh.
4. Optionally, try coffeescript. The language often promotes good, declarative programming. Once you get used to the shorthand, you won't go back. Don't discard it after spending a couple of days on it; it might take a little longer depending on your experience level. Another minor benefit, since there is a compile step some typos are picked up by the compiler.
5. One of the big benefits of Node is that you could move things like rendering from server to the client (or the other way round) relatively easily. But still it is cleaner to just have REST services on the server and handle rendering on the client (with say, Backbone).