And I can't comment on future versions or plans.
(the good news is that 32 bit float, is always 32 bit float in the upper levels of the pyramid)
Ah, well, thanks. At least you got the bugs out of the OpenGL-based display with 1 cache level.
I have exactly this same problem 2 years later (using CS6). Posterization on any zoom other than 66%/100%. It's a terrible bug as it also takes this into account when converting back from 16-bit to 8-bit (with dither) whilst retaining layers. It actually converts to 8-bit using the posterized data. I can be 100% zoomed in where everything looks smooth and dandy, convert to 8-bit and it looks like it did at 50%, but permanent.
The only way to get a good conversion is to flatten first.
So the bug is still there and/or worse than it was.
I will try this cache thing but my image is 1GB so not looking forward to that...The worst thing is I'm trying to do some subtle black and white work but I can't at the zoom level I want.