> I'm a strong believer that the combination of graphic cards and display
> should provide a gamma of 1.0: linear curve;

No, because it's better to have an 8bit number with bigger steps in 
brightness at the higher end, because that's how your eyes work.  If the 
difference in brightness between 4,4,4 and 5,5,5 were the same as 
254,254,254 and 255,255,255 (ie gamma 1.0) then we would see even worse 
"colour banding" for darker colours than we do currently with 8 bit 
hardware, and at the top end there would be an even less visible change for 
each step.

> number of bits per channel (I like 8, but you need a CRT; LCD do not
> have so much bits for all colour... and they might not be linear)

BTW inside most LCDs, the 8 bit input signal will be used to index a look up 
table (which contains the gamma and LC response curves), where the entries 
are 10 or 11 bit numbers that then drive the DACs that directly give the 
voltage to each pixel.  Very cheap LCDs only use 6 bits to index the look up 
table, and then have 8 or 9 bit DACs, but they are becoming rarer and rarer 
nowadays.

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