I have both of them and, although I am a Microsoft fan, I have to admit that Sony did a pretty good job with the Playstation Move. They are both very good devices, but the Kinect has a few advantages. As far as I've read, there are more games developed for the Kinect and Microsoft seems to have invested more into promoting their console than Sony has.
The Move has a much better tracking response; however, you actually do use a controller with that, unlike the Kinect. There is also a severe lack of games, I believe, compared to Kinect. So I would have to go with favoring the Kinect.