This megapixel terminology that we often see is just no good for describing the real photographic issues at hand.
In my humble opinion, topics that people really might bother to discuss are (in no particular order):
(1) actual resolution (MTF, lp/mm etc.);
(2) signal to noise (S/N) and continuity of tone;
and (the least definable of the three),
(3) character (which includes how the grain interacts with the composition, plus things like bokeh etc. that are quite subjective)
Would people kindly refrain from speaking in terms of megapixels! We are adults with a far broader vocabulary! Sweet cheeses, even in digital circles, reasonable people realized long ago that megapixel number is not The determinant of the value of an image.
If there were one word I could wish permanently banned from apug: megapixels.
<end of mini-rant>
Alright I got that outta my system.