Unless I'm mistaken... NPM gets installed with Node, so the instruction to also install NPM after installing node seems to be redundant -- or else out of date...? Also to get the npm install command to work, I had to restart (on Windows 7). Maybe worth mentioning that for those who aren't as familiar with this sort of thing. If you install node, then try to run that command without restarting, it produces an error.
My node noobness shines through -- I'll update :)
fix #12, no need to install npm separately