Why is it so amazing? The whole concept of the viral was closely intertwined with the equity of the product being mentioned (which is a game): "Wario Shake it Up." And it also says something about Youtube, meaning they're becoming more experimental and creative in advertising on site. (check out this insightful Techcrunch article which talks about Youtube planning to monetize its homepage more)
I wouldn't want to give any more spoilers so just watch it. :) Here is a screenshot:
