They are not DRM'd. They are very high quality and include the album art. I have been very happy with my MP3 purchases from Amazon.
A word to the wise, though: While they aren't DRM'd, I do believe that they are watermarked. A digital code is embedded within them that ties them to you. Use them on any device you like, that is fine. If you share them on the internet, though, they could be tracked back to you. To me, that is a great alternative to DRM. iTunes DRM can be cumbersome, and "PlaysForSure" was a complete freakin' disaster.
