It's certainly more difficult to dance the female parts than to dance the male parts. But women seem to be more naturally talented at dancing than men, so I think that may be a wash.
I'm guessing that really good looking men, like Mario, have an advantage because there's a lot more female voters than male voters and due to the easier dance steps for the men compared to the women. Perhaps Fred could give us a demographic breakdown on those rating numbers so that we could test that theory?
But I think that there's a lot of other weird things that happened this season that made more of a difference. 1) Jerry, who's really bad and Emmitt who's middle of the pack have been safe due to their huge crossover fan base from their real jobs. 2) Shannon who's not very good and Vivica who was decent didn't have the fan base to keep them around. 3) Sara would still be around due to her huge fan base if she hadn't quit. 4) The other two men are either good looking or good dancers or arguably both depending on if you like the Joey Lawrence bald look. So they have been fairly safe.
So this year I think it was more due to the popularity of the male celebs more than the pros they had next to them providing the embellishment and due to the one highly popular woman quiting. Also there were several couples with similar dancing ability so fan base has been even more important this season than in the previous seasons.