Japan has been selling the 250GB Xbox 360 HDD for a couple of weeks now, but there's no word on when it's coming to the States. A new dashboard ad hints that we might be getting it soon. Updated.
Of course, in Japan they're charging a whopping $US170 for the thing, so don't get too excited. If Microsoft decides to bring the price more in line with what normal people pay for normal hard drives this might be worth getting excited about, but I'm not holding my breath.
Update: The new HDD should be available as of today for $US130, according to Microsoft. It's cheaper than $US170, at least, but still twice as much as a standalone 250GB laptop HDD. Ah well. [Kotaku]