After reading Juul's game definition, I began to test his game definition on some of the video games that I play. First, I started with Legend of Zelda: The Oracina of Time and while thinking of Juul's definition I concluded it was indeed a "game" according to his definition. I also became more aware of the rules of the games and the abilities I was and was not able to perform with my character, which in turn made the effects of the games turn sour and caused me to quit the game earlier then normal.
The next game I played was Donkey Kong 64 on N64 which is an old single player game. You go through several levels of games with different tasks in order to free the other four monkeys in the game. You are then able to control the monkeys you've freed. After freeing them, you must then go back to each level and begin the search for five "golden" bananas for each of the monkeys for a total of 25 in each level. Juul's definition with its six game features, indeed held up once again during this game.
It's interesting to test games against his definition, to see if they hold up to his standards as a game. It makes me consider ever game I've played to see if his definition holds up, or if there is some weak spots in it.