iTunes will be getting a run for its money...
Competition is a good thing; and I am quite happy to see Amazon launch the beta of its DRM-free MP3 store.
Songs go from $0.89, albums can be <$1 to >$9; and did I mention no DRM?
This is really going to hurt CD sales; at $8.99 without DRM for Top 100 albums, a lot of people are going to buy the 256kbps MP3 albums and burn their own CD's - not to mention load up their iPod's etc.
Well done, Amazon.