Sure. Wii Fit Plus, EA Sports, Walk it Out -- my heart rate monitor has it comparable to beginner DVDs I do. They have a place in the spectrum.
I have no illusion that these games will match an advanced DVD or formal gym workouts but that's another place in the spectrum.
For me? It is fun and gets me moving again. More important -- I can include my kid. That matters to me more this time around that when I lost significant weight in my 20's before she existed!