So here is the spectral distribution of d65 (image from wikipedia).
for the specific intensities, here is the official document from the CIEhttp://www.cie.co.at/publ/abst/datat...2004/std65.txt
When measuring colors we take the spectrum and apply a color matching function against them to get XYZ values (colorimeters shortcut this process by trying to emulate the Color matching function with their filters). Those XYZ values we then convert to x,y values to plot in 2D. The Y from XYZ is what we use for luminance.
So here is a Dell u2410 IPS panel calibrated to 0.3128, 0.329
Here is a Dell 2408wfp PVA panel calibrated to 0.3129, 0.329
While similar they are significantly different. I mentioned above color matching functions, the way they work is that the area of the spectrum under each curve is summed up so the area under the X curve is the X value, Y, Z ect...
Here is the 2408, with the standard 1931 2 degree colormatching function laid ontop.
So as long as the areas match your eye SHOULD see the same "color". But the Color matching functions are just approximations but everyones eyes are a little bit different, so you would notice a difference if the spectrums are significantly different.