okay wow, it seems Youtube ain't fucking around anymore when it comes to copyright stuff. Apparently now, if you've got anything uploaded that infringes at all and they happen to catch it, not only of course is it removed and you get a tag on your account (nothing new there), but also you've got to take a little like 5-6 question quiz on how to handle and respect copywritten material
Granted I'm not sure what happens if you get any of the questions wrong, I got all right (not like they were super complicated), but you have to complete the test before youtube allows you to then do anything else on your account.
It is pretty cool how more and more companies seem to be lightening up quite a bit on letting fans use stuff, particularly for the different mixes and mashups, that are all done just not for any profit and for the love of the material. It still cracks me up though when I see someone's gotten at the end of their description that no infringement is intended at all, and that this shields them. If you're not trying to make money when using someone else's IP, then great, but that little disclaimer itself isn't securing you