I (Robin Ek The Gaming Ground) has watched Youtube videos since 2005. And i think it´s safe to say that the Youtube demographic landscape has changed a lot over time.
Let´s just say that it´s no coincidence that Youtubers such as "Pewdiepie" and "Smosh" has become huge Youtube stars (childish content for little kids). And why is that? It´s because children has taken over Youtube. It´s even said that 30% of the top channels on Youtube (right now) are literally channels for little babies.
And this is my (Robin Ek The Gaming Ground) take on this subject.