If Jordan or Natalie win BB11 USA; the USA will have four female winners as well:
Lisa (BB3), Jun (BB4), Maggie (BB6)
However Danielle from BB3/7 made a good point about the US version that the only way for a female to win is if there are only female in the final two. Everytime there has been a male/female final two the male has always won. Although if Jordan makes it to the final two I can see her getting two guaranteed votes (Jeff/America).
I wonder what the record is for male winners. I know the USA has had 8 male winners from 2000-2008 (Eddie, Will, Drew, Mike, Dick, Adam & Dan)