If you develop with Node.js and you want to be sure to have the latest stable version, luckly there is a PPA for it. All you need is to follow these instructions:
sudo apt-get install python-software-properties python g++ make
sudo add-apt-repository ppa:chris-lea/node.js
sudo apt-get update
sudo apt-get install nodejs npm
That's it!
Reference: https://github.com/joyent/node/wiki/Installing-Node.js-via-package-manager