Raspbian is based on of Debian Wheezy, so things are a little different than the standard Ubuntu 14.04 installs. Remember to always read a script before you curl it to bash.
curl -sLS https://apt.adafruit.com/add | sudo bash sudo apt-get install node
Now check it's running okay...
pi@raspberrypi ~ $ node -v v0.12.0
Ok so it's a little behind but still on 0.12.X.