Stephanie Lenz has posted a YouTube video of a baby dancing to the Prince track "Let's Go Crazy" . The EFF has started a legal case to protect her right to include the soundtrack although there is a claim from Universal that the video should be taken down because of the Digital Millenium Copyright Act.
My speculation is that this may have something to do with Prince or his management and that Universal may follow a different policy in similar situations with a different artist. I am not claiming anything new as fact.
During this year a video I had loaded of the Mama Stone House Band covering I Wanna Be Your Lover was removed from YouTube following a request from Controversy Publishing. It had already been public for several months. So I think something may have changed in YouTube policy. They may be closer to official sources than when they were building an audience. I have been unable to get a reply from YouTube or Google about my bad status. I now am back to a 15 minute limit and cannot choose Creative Commons as an option. I think it is rare for artists to object to cover versions but I would like YouTube to explain this. There is a lot of uncertainty as far as I can tell. It seems to be a matter of chance whether Prince related video survives.
Meanwhile there is continuing interest in Content Marketing, using free content to reach an audience and gain interest in new product. Content Marketing is predicted to continue in 2014, see this story in Search Engine Watch. There could also be more than a few instances of Reverse Content Marketing - use search to find the fans, then make life a misery.