It seems that JibJab, the producers of the Flash film below, has gotten into some hot water over fair-use rights of the song This Land is Your Land by Woody Guthrie. Personally, I don’t see this as a copyright violation, since it’s not in any way inflammatory and is used as a component of the movie itself. Admittedly, it is a central part of the movie, which is where this gets a little hairy.
This has been wildly popular on news media outlets, and none of their lawyers seemed to have a problem with announcing its presence. If they had thought it was an illegal thing, would they have mentioned it in the first place or just forwarded it onto legal teams?