Are all the best games NP-hard?

Catullus writes: Following in the footsteps of Tetris and Minesweeper, the simple yet addictive multiplatform game Flood-It is the latest puzzle to be proven to be hard — NP-hard, to be exact. This means that there's no way to write an efficient program to beat the game, unless P=NP. This research by computer scientists from Bristol University raises the intriguing question: are these games fun precisely because they're hard for computers to solve, and need a spark of human creativity?