Reports state that Apple is working on an arrangement with Music Labels to allow users to download unlimited music from iTunes. How does this works?
Well currently, you can buy songs on iTunes and if by any reason you loose it and you don't have it backed up in your computer or an external drive then you loose them. If you try to download it again from iTunes it will cost you. In the present it doesn't work like apps, where you can have them in as many devices you have and download them as much as you need with you Apple ID.
This is a very welcome feature because if by any reason you loose a device or computer and plan to get your music back then it wouldn't cost you. It will allow you to download songs on as many devices as you own at any time.
We will wait on more news about this.