Assuming Amazon can execute a global rollout sooner rather than later, this is also potentially bad news for Apple, which has held a near-monopoly on online music since the launch of the iPod. Apple's iPod's sales are slowing rapidly--unit sales missed analysts' expectations in Q4--and an erosion of iTunes's dominance of downloads will open the door a crack for hardware competitors.
(Not that Apple has anything to worry about in the near term: As of this writing, on Amazon, 9 of the top 10 bestselling music players are iPods.)
Perhaps it's Sunday-morning brain fog, but it's not immediately obvious to us why Amazon would break with its announce-it-when-you-launch-it tradition to issue an airy release like this. Usually it's the industry leaders who follow this communications strategy--to deter would-be upstarts--and Amazon's not the leader in this business.
Update: One explanation for Amazon's early release -- an attempt to get Universal Music Group fully committed?
See Also:
Amazon Signs Sony, Now Has All Four Majors DRM-Free
How's Amazon's iTunes Killer Doing? Well, Actually