Viacom v. Youtube

I really enjoy watching Japanese shows on Youtube. Almost every night I look for something interesting on Youtube. However, from the aspect of copyright holders, Youtube may be an annoying tool. Concerning Viacom v. Youtube, I thought at first that Viacom was trying to protect their content which are copyrighted and owned by Viacom. However, some articles stated that Viacom’s real aim may be to protect their new business, which is to work with “Joost”. (Viacom’ divisions, such as MTV networks, provide Joost with television programming, that users can view using the Joost platform.)
It seems that this lawsuit’s basis is how to protect their new business model in addition to the issues concerning how to promote the innovation of new technology and how to think about DMCA or fair use. I personally support Youtube, but I need to know the interest of other new business models also.

On the other hand, we actually see copyrighted material on Youtube, which are obviously beyond the scope of fair use but left as they are. Because of business strategy, the copyright holders may leave this kind of illegal usages without taking any legal action. Professor Tim Wu at Columbia University calls this usage “tolerated use”. These usages sometimes give the copyright holder benefits which may play a role as an advertisement of copyrighted works. Even if we admit such a usage, “tolerated use”, it is still difficult to keep balance between the copyright holders and innovators.