As far as I know, and I may be wrong here, iTunes will play standard mp3's. At least mine does. So what would the "...a great alternative to the DRM ridden iTunes..." gain you? I would rather have a player that can play drm'd songs, if I were forced to play a few, and still be able to play standard mp3's.
The problem with iTunes (and one that I am hopefuol Songbird will not have) is that you are limited to MP3 and Apple's AAC format; perhaps a couple of others that I don't care about too.
I'm not crazy enough to care about OGG, but I do have a large amount of music in FLAC format that I'd love to be able to load onto my iPod (dream on), but failing that at least being able to manage it in a nice front-end like Songbird will be a plus.
