Playing the Wii should count as exercise!
 

Especially when you play it like I do. I flail like a crazy person, especially when I'm playing Legend Of Zelda Skyward Sword! You actually have to really swing the wiimote like a sword. It's nuts! I say they should add that to the list of "activities"!

I would just log it under one of the choices in the Conditioning category.

Even though there is no spot to add it as an activity. I'm glad you posted you play wii to get a work out. I use the wii fit too to get in extra activity. My doctor feels it's a great tool to add to any inside workout and when you can't get outside to workout because of the weather. I use the wii fit free run, but instead of running I walk.

Well I play a game, but it does get me in the zone. Swinging a wiimote like a sword to kill a monster as Link should definitely count!