I love firefox there is always a way to get rid of annoying crap no one wants to have.
If you happen to be using Firefox, you should also have an extension called AdBlock Plus. You can get it at adblockplus.org/en/
installation, and make sure you get the element hiding helper also.
Once that's installed, you go to tools -> adblock plus preferences and click the "add filter" button, and add these filters:
youtube.com##DIV#quicklist-tray
youtube.com##DIV#quicklist-bar
youtube.com##DIV#quicklist-bar-container

