The only reason Sony doesn't go after Orb is because there's simply not enough meat on them bones to make it worth it. You don't see Lions hunting ants either.

Amazon on the other hand is pretty meaty and juicy, lots of cash to bleed.
Sony and many other record companies don't see any kind of format transfer as acceptable - that's nothing new. That means you buy your music in one format or medium and it must stay there unless you buy it again. And when you buy MP3s, they'd better stay on your computer or iPod. Sad, but that's the way it is.
Maybe they're trying to say that since the info comes from the cloud that it's amazon re-broadcasting the content. For which they likely don't have the correct licenses, yadda yadda yadda.
It would be nice to see Amazon and Apple get into the music publishing biz just to give these guys a reality check. But, I don't really wish for that because it's the slippery slope thing again where these guys (Amazon and Apple) just get more control to exert over other much smaller guys who don't need to be slapped around.