The feature length documentary by 2 Player Productions chronicling the genesis of the Minecraft phenomenon.
Direct link to video
A great look at the people behind the game as well as the worldwide community that's sprung up around it - chronicling their efforts to get version 1.0 of Minecraft out the door in November, 2011.
According to Wikipedia, as of October 23, 2013, the game has sold over 12.5 million copies on PC and over 33 million copies across all platforms
There's a great quote from Peter Molyneux in the documentary, creator of many great games such as Populous, on why Minecraft is such an important game in this time:
Lego at the moment is like traditional game design. Buy the box, open the box, turn to the instruction sheet, make the model, stick it on the shelf and buy the next box. That's exactly like traditional game design - buy the game, go through the challenges, finish the challenges, stick it on the shelf, buy the next game. Where Lego used to be just a big box of bricks and you used to take the bricks, pour them on the carpet, and then make stuff. And that's exactly what Minecraft is. There was no instruction booklet.
If you watch nothing else: