I bet that if one looked at the contracts between Google and Universal, one would find clauses binding the signatory states to undertake such copyright wars. Now that YouTube has built up its viewership, perhaps largely on the basis of a casual attitude toward copyright, it makes sense for it to pull up the ladder. No one is more vehement in support of property rights than a buccaneer who has gotten rich. Besides, as a simple matter of competitive balance against other deep pockets, such as Sony, if YouTube must incur the ongoing costs of carefully tiptoeing down the path of righteousness, then it has a strong interest in being sure that others must incur similar costs. These developments will not prevent new sites from arising, but it means that such sites must start with pockets deep enough to engage in the monitoring necessary for compliance. They will also probably be forced to get licensed from the get-go for the inevitable violations Legal compliance as a barrier to entry! Personally, I love it, because it is so wonderfully entrepreneurial.
I can think of a number of words to describe this strategy, but “entrepreneurial” isn’t one of them.