I say Kudos to the BrightHand readers that kept emailing and asking questions about this. Only when people started emailing Sierra Imaging and asking what's up, did HP get forced into an admission. So it won't matter to some people. And to a percentage, it will simply be unacceptable. It's a built in evolutionary trait from a long distant time when good color perception meant the difference between survival in the wild or death.
Times are different now of course.
This can still be fixed in software. Sierra Imaging could create an option for their HP only versions that not only optimize the 12bit palette, but software dither the images displayed as well. Of course it would only affect color images displayed while in their program, IE and other apps would be unaffected. But I always say, do not underestimate people's perception of color. It's more important than you think.