Er, because the Japanese are more prone to paying top dollar for no reason? Maybe too many of the non-audiophile crowd can't decipher the difference between the S430/S630/S730/A720/A820, so they all bought the cheaper players, and so Sony only brought out new products at those price points.
Having said the above -- I haven't seen what SonyInsider says -- but I think there's still hope for this thing to be released worldwide. Volume-wise Sony still can benefit from selling it worldwide, even if it's a very small number compared to the ipod or the PSP.
ATRAC is on its way out... sad, but I feel very strongly that fans should blame Sony for its demise. They could have very easily released a standalone encoder/player software for it, if they really wanted to popularize it, and NOT let any one of us need to have a debate on whether SS is an "easy" software, don't you think?
A couple years ago Sony said it's too much work to let ATRAC and drag&drop coexist, but that turns out to be a lie if you see it from a 2009 point of view (it's done now, and it works as two separate libraries, so there was no issue to begin with). You should also know that Sony's VME technology has always been modular, so they can simply drop in the ATRAC codec and it should work. If I may be so bold to say, I think too often some of these decisions are based on factors other than what we want.