Today, Apple released its first “iTunes Plus” tracks, music in 256 kbps AAC format with no DRM. So you can copy this music to any computer, play it on any device or computer that supports AAC, with no restrictions. However, while there is no DRM (digital rights management) in these tracks, there are breadcrumbs.
If you look into an iTunes Plus file–just open one with a text editor–you’ll see both your name and your iTunes account ID. Here’s an example of my name showing at the beginning of the file:
And, here is where my iTunes account ID shows up (I’ve replaced the actual ID with XXX@XXX.XXX:)
You’ll also see this information in the Info window for the tracks in iTunes.
So, while nothing is stopping you from sharing these files, remember that anyone will be able to find out who initially bought them. You can most likely edit the above information with a hex editor, but I haven’t tried that yet.