I think you'll need to evaluate after you take a class or two! For me it didn't do much, although it was really enjoyable. I think because I was a dancer for a very long time I didn't find it challenging enough (and perhaps the instructor wasn't working us to the best of our abilities)... In that respect, everyone and every class is different. But like Ilene said, if it gets your heart rate up and you like it, then go for it!!!
Any movement at all, if you can keep up with it, is good for you! I hope you have fun!!!