Can't you understand the idea of limited space forces Nikon to use
approximations? It's not the metric system that Nikon is using, its
the Nikon D80 abbreviations that it is using. That's why 1.0K on a
Nikon D80 indicates there is space on the SD card for between 1000 and
1099 shots available. How do I know? Because the camera shows 1.0K, I
take 30 or 40 shots and then magically, the camera no longer reads
1.0K -- the camera tells me there are 999 shots left.

But don't take my word for it. Look at the manual for the D80
http://www.nikonusa.com/pdf/manuals/noprint/D80_noprint.pdf
and scroll down to page 17 of the .pdf (which oddly is page 5 of the
manual as many of the early pages have Roman numerals)

According to THO  <tho@tho.tho.23.invalid>:

    Well ... there is a difference between 'k' and 'K'.  In the
computer field, lower case indicates a multiplier of 1000, and upper
case indicates a multiplier of 1024 (2^10th).  But we can ignore that
for the moment.

    However, in scientific fields. the use of a 'k' suffix in
combination with a decimal point and not sufficient digits to fill out
to the end means an approximation or a range -- such as was given above.
Think of it as (for the "1.1K") as 1.1 times 1K, and since there is only
one digit after the decimal point, it leaves an uncertainty as to the
remaining two (missing) digits.

    In electronics, you can buy a 1.2K resistor.  Does this mean
that if you measured it you would get precisely 1,200 ohms?  No -- most
of these resistors have a tolerance affixed -- with the carbon
composition resistors having tolerances of 20%, 10% or 5%, allowing (for
the 20% case) a range of from 960 ohms to 1440 ohms.  And the actual
value changes with the temperature anyway.

    This display is just the same.  It is a guess (estimate) anyway,
nobody knows how many images you will *really* get in there -- and it is
almost certainly going to be greater than the number specified (let's
assume that the readout is now saying "999" -- a precise number -- but
it is almost certainly *wrong*.  Nikon has made its estimate on the
conservative side, so you can't walk up to them as say "It said that I
could get 999 images and I only got 950 images -- your camera is
defective."  

    Nikon does not *owe* you, me, or anyone else, a precise count,
and the manual (you do read the manuals, don't you?) will tell you that
it is a rough indication (and will tell you the range which given
indication covers).  Since there is no way to be certain of how many
images it will actually hold until they are taken, what is the need for
wasting space on the top readout to try to be more precise.

    Why not simply assume that the 'k' displayed is actually a
distorted '+' and forget this thread?

    Enjoy,
        DoN.