They have not, but 128k AAC files are said to sound better than 128k MP3s. It's probably not all that much of a difference, but I am happier with the AACs I've purchased at 128k than the MP3s that I have at 128k.
However, Bren will not deign to touch an Apple product, so he'll need to look somewhere else.
As far as purchasing music goes, you'll have to go with WMA with DRM if you want anything mainstream, Bren. For non-mainstream stuff, there is another store that does sell unprotected MP3s, but I'm not remembering what it is off of the top of my head. I'll post back if it comes to me.
The WMA stores are probably largely similar, since they all use Microsoft's Plays4Sure licensing, files, and DRM.
In short, you're probably better off buying the CDs and ripping them yourself.
