It' works on Leopard too! I have Leopard, and I can play videos (avi and MP4 only) and music (mp3). But, you can not use the spootlight for that, you MUST navigate through your directory (Files icon), and once you find the music or video (avi) that you want to listen, just click over the file. You will see the video/music streaming/playing into yout iTouch. It's a wonderfull program, because I could streamn an avi file with 1:30 hour (1gb) of video without any interruption and high quality of sound and image. This is a killer app.
Very nice, and YES it works with Leopard as well.