Actually the title should read, "You'll have more fun with blondes in B&W".
For the record, I'm a sucker for brunettes, but blondes photograph fantastically in B&W especially if they have highlights. For the following reasons:
1) Light color hair provides great fill on the darker portions of the face = more even exposure
2) Blonde hair (particularly with highlights) photographs with natural contrast. See the following examples:
See how the highlights pop?
Save a kitten, shoot a blonde :)