Games
How to resolve AdBlock issue? 
What is the difference between a good game and a great game?
I think the answer, after years of sort of feeling around it, is emergent gameplay. It is the one characteristic that every great game that I can think of really shares on an innate, design-level basis.
Emergent gameplay means that the game lets you actually play it- it gives you a framework, but the actual gameplay comes from what you do, how you respond to both mechanics and other participants, and what you collectively create when you play it. The game emerges from what you choose to do and how you choose to interact with it. It isn't dictated to you through clever rules, controls, and instructions.
Obviously, a game like POWER GRID or AGRICOLA features this concept to a much lesser degree whereas a game like DUNE (pictured) or COSMIC ENCOUTNER are almost completely founded on emergent gameplay ideas.
Of course, the article is at a video games site and it's interesting that it's just been over the past decade or so that video games have sort of developed along these lines. Hobby games have always had it in some measure, although the Eurogame Dark Ages (1999-2005) almost crushed it out of existence by telling us that player interaction, luck, and imbalance were somehow design flaws. The AT revolution redressed the balance, and I think that the rising popularity of co-op games in particular shows that emergent gameplay is one of the things that most people really want out of any kind of gaming- other than fun murderers dead set on perfect balance, perfect information, and perfect boredom.
