Kinda slow reply, but I just saw your post. You can get a great workout from the Zumba kinect game. I enjoy mine. It offers mutiple workouts per difficulty level & time frame (20-, 45-, 60-min; beginner, intermediate, advanced). As for quality of workout, I'd put it up there with the Zumba dvds. You'll really sweat once you get into the moves. There's also the video game aspect: keeping completing workouts to unlock more routines
I like it and think its worth it, if you have the budget. The kinect picks up moves decently.. Dance Central was fun too, but not near the workout of Zumba. There's also 2-3 more kinect fitness games that should be good for exercising at home. Just make sure you have a big open space in front of tv (6-8' square).