An interisting video.

Title: "Uncertainty in Games" Greg Costikyan, Playdom

We try to avoid uncertainty in our everyday lives, but uncertainty is a critical element in games. If there's no uncertainty about path or outcome, the game won't hold our interest. Uncertainty can, however, come from many sources -- random factors, hidden information, difficulty of perception, and strategic complexity among them. In this talk, I will analyze a number of very different games to uncover where they produce uncertainty and why this engages players; discuss many different types of uncertainty; and suggest ways that designers can add depth to their games not only by tuning existing sources of uncertainty, but by adding additional ones.