I second this, its excellent, i use it on my iPhone however. its a lot easier than using iTunes.
With a combination of pwntunes, photosync and dropbox I haven't used iTunes for a long time!
addiosamigo, do you use it for videos as well? I've had a play with the trial version and I can't work out if it's possible to use it for videos. It seems like it's geared towards managing music, and using the iOS device as file storage.