I think they use blondes mostly in those magazines 1) because it is stereotypical that guys prefer blondes, but 2) because blondes are stereotypically more "wild and crazy" and sexy than brunettes. I mean you say the word brunette...and people typically think "businesswoman" or "librarian"...say blonde and they think model or sex. It's all based on how it's advertised. I do think that magazines and the media (TV and movies) are getting away from this slowly.
I like dark haired men....even better if they're tall!!!
