This could open up a new channel for attacks against web sites. Forget about those that are just posting content with the intent of sharing. What about those that simply post/upload copyrighted content with the sole intent of bringing your site down.
Another thing that occurred, was that there is so much of this going on today, that unless people drastically change their habits, or courts are very selective with who they prosecute, every owner of every site on the web will end up in court.