It works for me, I can pause and play and pause and play:
As I also use ClickToFlash (Flash blocker), I can play the less CPU intensive audio stream, which I can play and pause too.
And I heard something too, btw.
So it seems to be that Apple only neglected to fix Safari for Windows and Linux users. If for PR reasons alone, they should pay more attention to site usability on these other platforms too (especially for 5 year old browser tech.)
Safari for Windows has historically sucked, so I'm not really surprised (after 3 versions it still can't handle the proxy server at work). There's no Linux version that I'm aware of so I'm not sure what you're talking about there.
While there are several current minor browsers on the Linux platform that don't support streaming MP3 web players, Safari seems to the significant laggard on Windows.