Madonna videos are disappearing from YouTube. So are ones by R.E.M., My Chemical Romance, Green Day and Josh Groban. That's because their label, Warner Music Group, has pulled all its music from YouTube.

Negotiations between Warner and YouTube have fallen apart. Warner says in a statement it's working with YouTube to find a resolution that would allow the return of their artists to the site, but until then, it can't accept terms of payment to the artists.

YouTube has apologized to its users and says, "Sometimes, if we can't reach acceptable business terms, we must part ways with successful partners."