Apple have the best marketing department in the world. More or less.

Nobody cared about AAC for four years, and now it's all you ever hear. It's funny the only reason they used it was because the record labels didn't like the negative connotations of the MP3 "brand" and of course Apple wouldn't touch WMA. Technically it's on a par with WMA, MP3 Pro, Ogg Vorbis etc.

Currently there's little reason to add it to a player except to support iTunes Store content. As you pointed out, this won't work anyway as it is wrapped up with DRM.

Rob