I'm jumping in on this conversation. I really think it's 50/50. I've worked as both a model and a photographer.
From a modeling perspective I'd say I prefer a male photographer. There is this thing about women being judgmental that I hate. Most of us remember changing in dressing rooms or locker rooms in front of a whole bunch of women and feeling like they are tearing us apart or comparing us with their eyes? For me personally, I think that's why I prefer a male photographer for modeling. I feel like that males are less judgmental most of the time.
Now, as a female photographer, I can say that for women who are not professional models almost 75% of our clients request a female photographer. For them it's almost the opposite. Having a female photographer is less worrisome to them.
My fiance shoots probably more boudoir than I do over all, but most of them are professional models. The tables just seem to turn when it comes to brides and the general female public. I also think it might depend on where you live though, some states I think women are more conservative than others and in the less conservative places there probably isn't any sort of gender preference about photographers.
The other thing though is that the number of male photographers shooting boudoir is still much higher than the number of female photographers, which I think might be another reason why a lot of the boudoir photography is shot by males. I haven't seen any statistics on that, so I can't say for sure, but it's a thought.
Maybe we should put up some polls on this? I'd be curious what brides would say.