The blind listening test at hydrogen audio is not telling us what sounded the best or worst, it is simply telling us which samples had the most noticable differences from the original.
I suspect if they did a test asking the listeners(not experienced testers as they wwould be listening for artifacts) to say which was the most pleasurable to listen to atrac would fair better.
I believe Sony have created a codec that is very easy to listen to , at 132 atrac does not sound the same as a cd it is coloured , smoother with less spikes and in my opinion is a pleasure to listen to.
If you read reviews of the different music stores (T3, Stuff etc) , the same thing keeps coming up "atrac sounds better than mp3 and AAC , shame you have to use a Sony" is the general concencus.