I have been using this great game for about 4 months and am a good 15 pounds under my first weigh in. Though I was not the most dedicated to losing weight I still did great and can say that Wii Fit is a great buy for the lazy gamer such as myself. It is not only a great tool but really fun as well. My only complaint is that I wish it had more Aerobics games such as the Boxing and Jogging but there is still a ton of games to choose from. I have yet to really get into the Yoga or Strength training exercises too deeply but that is my focus now so i may update this post in a few months about it. If you wanna lose weight and have a Wii go get this game!
If you have the regular version of Wii Fit then i advise you go upgrade to the Plus version. Your data will transfer plus there is a whole lot of new games and content.
P.S. Watch the guy holding his dog near the end of the video, i thought it was pretty dang funny!