I own both the Wii Fit and Jillian Michael's Ultimate 2009 workout program.  While the Fit targets particular areas, Jillian Michael's program is more in tune with making you sweat and getting your cardio working.  I have been using both programs in conjunction to DDR and have lost over 20 lbs in about 3 months.

At first some of the workouts were hard to get but I have taken the time to understand how it all works and it's all coming together.