Up until my most recent story, I've only ever written novels from the female perspective. That makes sense to me, because I write the way I think, but in my most recent novel I challenged myself. I wrote from three different perspectives, and one was male. Therefore I had to create three different voices and understand the female/male distinctions.
It went pretty well, I think. I was told from some of the guys that have read it that I got the male perspective down pretty good. It wasn't entirely different from writing female perspective. There's a large plotline that affects all perspectives, but for the most part the chapters from Neil's--my male character's--perspective had a different setting that also helped distinguish it from the two female characters.
I think I still have a preference for writing from a female perspective, but I feel good doing whatever lends itself to the story the best.