A large proportion of Minecraft players are kids. I've written about this in The Minecraft Generation: A distinct demographic cohort. [1] This will be the first generation of children to grow up with a lot of experience in virtual worlds.
Not really, plenty of kids have grown up on WoW or EverQuest or LPMUD or whatever before this, not to mention so many other games. I don't see how Minecraft is revolutionary in this respect.
Minecraft isn't "plenty of kids." Minecraft is millions of kids, all playing the same game. Sales are over 26 million on all platforms, 10 million on PC. If 30 percent of PC sales are played by kids, which I think is low, that's 3 million. Plus a lot of kids are playing pirated copies or on other platforms.
WoW was popular with kids, but there were never 3 million children playing it. The majority of WoW and EverQuest players have been adults. MMOs, even kids MMOs, are unmodifiable theme parks which don't hold a child's attention for very long. Free Realms, the MMO made by Sony Online Entertainment targeted at kids, had to run TV ads to remind them to play[1]. Meanwhile Mojang has spent zero dollars marketing Minecraft (if you don't count Minecon expenses). Viral spread among children has helped make it the seventh highest selling PC game of all time[2].
MMOs have numerous specialized blogs covering them; the popular MMOs have dozens of blogs devoted specifically to each title. Minecraft has almost no blogs covering it because blogging is an activity done by adults.
In contrast, searching YouTube for "minecraft" currently yields "about 70,200,000 results." Instead of reading, most children would rather watch a video and quite a few have mastered making and uploading their own. One top YouTuber specializing in Minecraft makes enough to earn a living off it (he's young and single), and he's still gaining subscribers[3].
Minecraft is different. There's never been a game like it.
[1] http://gamegenus.blogspot.com/2013/05/the-minecraft-generati...