[VergeOfDiscovery]

This article suggests that such bias made it into the MPAA rating system (even more so) after parents complained to the board about the content in Sacha Baron Cohen's Brüno - so now they'll specifically flag whether you're going to be exposed to penises - "an odd distinction that isn't made when actresses disrobe."

http://www.vulture.com/2010/10/mpaa_now_specifically_warning.html