I don't buy into Google's defense that what they show is not their responsibility because it is always their responsibility regardless of the source. It's their domain. It's their service. It's (hopefully) no longer going to be a platform ripe with copyright infringements. (Pinterest are you paying attention too?)
The Megaupload guy found out first hand how much the content he allowed to be uploaded was his responsibility so I'm fairly sure this will mean some rather drastic changes are on the horizon at Youtube now. If they aren't they should be.
Take that last sentence with a grain of salt, I'm fed up with seeing crappy and often irrelevant 30 second youtube videos appear above my best articles in search results.