DoubleTwist, with a Twist of Amazon

"Doubletwist is now powered by Amazon's 5 million strong music store in support of its vision to connect consumers with all their media across any device. Amazon access is only available to US users from the Mac-only software at the moment. A PC version is "coming soon" along with more country support."

Both iTunes and the Zune desktop each link to their respective stores, but what is a MP3 player agnostic supposed to link to?  If you said the Amazon store, you win a prize.  It makes perfect sense.  Amazon doesn't care what MP3 player you use.  From the perspective of DoubleTwist, this helps fill in a feature they were missing, and I'm betting they probably have an affiliates agreement with Amazon to help bring in some money.