And actually works?
I'm sure Wii Fit is a ton of fun and might help you lose 10 pounds, but honestly suggesting it can really help you become fit is sort of weird. I'm not even strictly talking about weight loss. I don't really see anything Wii Fit itself would help you do to "get fit" that you can't do cheaper or better on your own, except for the stat tracking stuff...but it seems to use BMI. Although you can switch it to show weight, that would imply you expect it to help you lose a lot of weight and we're back to step 1.
Though I think the yoga stuff looks cool. I'd buy a more serious fitness game if one was ever made. I don't know what kind of capacity games have to do this though.
edit: I am not even accusing it of being a nongame so i don't even care about that