I'm in love with the Kinect! We have Dance Central and Your Shape, I tend to vary which one i use when I work out just so I can have some variety. Even with just those two I get a really nice workout, though the hula hoop game on Your Shape often irks my nerve.
I think the Kinect is great thing for people that want to get a good work out but maybe aren't comfortable enough to go to different classes at the gym and such. I don't fit into that category but I won't play DC if anyone else is in the house simply because I look like a fool.
I was looking at getting the EA Active 2 just don't know anyone that's used it so I'm on the edge.