I have never had a YouTube channel shut down for using copyrighted music.
I once had the music removed from a video and they guided me toward their free music section, but usually they just give you a copyright notice and guide the viewers to iTunes to buy the song.
I have had a channel shut down for abuse of TOS (terms of service), but that was to do with my political persuasion. I had no warning, they just shut it down, meaning I lost over 2 years hard work. I now back everything up just in case.