youtube download entire playlist

http://askubuntu.com/questions/376268/how-to-download-entire-youtube-channel-using-commands-or-application

Use youtube-dl command to download videos straight off of YouTube.
To download an entire channel

youtube-dl -citw ytuser:<USER>

To download all videos on a playlist

youtube-dl -citw <PLAYLIST URL> 

youtube-dl bug fix & latest release:

http://rg3.github.io/youtube-dl