An overhyped game with massive flaws that you will notice over a period of extended use!
Wii Fit has been constructed very badly. It does not tailor make routines to suit each individual user thus you have no idea what part you should be exercising and how frequently. This causes an uneven development of the health of the body and can cause weakness is some areas whilst strengthening others. It has a very low number of exercises and because of this you exercise the exact some area each time. This does cause repetitive strain injuries. It does not include any warm ups and does not tell you how you should do them. It just says to do it and for those who haven't a clue how or for how long this can lead to injuries. It has the same music every time and the graphics are very weak and bland. Everything is just white, including the trainer! This makes the whole thing start to become very boring after a few months. BMI has been found to be very inaccurate at measuring health and fitness and since this is the only way that Wii Fit measures it you are never given an accurate account of your health development. And finally there is the price. Wii Fit costs ₤ 70 or more. This is because of the Wii Balance Board which I have found to be completely unnecessary as ALL of the exercises can be done without it.
To sum up. Do not be taken in by the hype as it does not appear to have been developed to actually assist with fitness over a period of time but rather causes injuries and uneven development of which is inaccurate to track in the first place. Don't even get me started on the ever yo-yoing daily body test. Avoid if you can and purchase an exercise DVD or My Fitness Coach for the Wii instead.