Google has implemented a new system that auto detects content that is supposedly in breach of copyright this week, and it is affecting many YouTube stars. They are claiming that dozens or even hundreds of their videos are being removed. Since these claims are automatic because of the new system, many game companies who own the copyrights in question are doing their best to help those affected by the new system.
YouTube star TetraNinja (500,000 subscribers) claims that more than 350 of his videos have been taken down; GhostRobo (more than 600,000 subscribers) says more than one hundred of his videos have been removed; and YouTube star TheRadBrad (nearly 2 million subscribers) claims that "every video I've uploaded since 2010 is slowly being taken away from me." Since these and many other YouTube personalities rely on these video to generate income, they are clearly very concerned about Google's new policy; getting a video flagged for copyright means a loss of revenue while Google decides what to do.
Game companies like Blizzard Entertainment, Deep Silver, Capcom, and Ubisoft are siding with YouTubers because many of the new claims are part of the automated system and not something they are involved in. Some are urging users to dispute the claims.
Details on how to go about that - depending what your content is - can be found in this excellent CVG report.