THE THREAT AND PROMISE OF THE UNKNOWN
Margaret Robertson's Gamasutra feature about her experience with Minecraft is basically amazing. It's not just her excellent prose, which took me back so vividly to my own first experience with the game. It's her deconstruction of the design principles that make Minecraft work, presented with such clarity as to make me feel like a bit of an idiot for spending as much cognitive energy as I did trying to tease out why the game is so damn compelling, and not arriving at much of a satisfactory answer of my own at all.
Forgive me for cribbing so liberally, but here is the crux of it: