Bungie is throwing the option out there for Halo 3 multiplayer, as part of custom character design, to allow players the option of having a Spartan warrior with a female voice. They aren't promising this as an option, but are merely opening up the conversation for discussion on their boards. And they want to hear from the ladies, saying, "If you ARE a dude, we don't care what you think, because we're not asking you. Anyone who says anything stupid or sexist in the discussion forum will be megabanned."
GayGamer.net has a running joke regarding Ellen DeGeneres playing the Master Chief and defying stereotypes. Bungie did cast Michelle Rodriguez (LOST, Resident Evil) as a soldiers voice in Halo 2. It's certainly interesting to see Bungie take the testosterone soaked genre of first-person shooters, amplified by 1000 when in multiplayer, and give it a twist. It's actually not that far of a stretch, anybody who played Metroid Prime looked at the world through a woman's eyes. Also, considering there is always a 12-year-old with a microphone in deathmatch, listening to those pre-pubescent cries means we listen to women's voices all the time anyway. Hey Bungie, go for it, most gamers prefer listening to the battle cries and death moans of a grown woman than a 12-year-old boy.