In an interview with CS-Nation, Robin Walker was talking about TF2 about the new Pyro unlocks.
CS-Nation: (From: various) What is the next class set to receive new unlocks and achievements?
Walker: The Pyro is the focus on the next
pack. We’re making some significant changes to the base Pyro class
& weaponry, in addition to the three unlockables and thirty-five
achievements. We’ve never been terribly happy with the Pyro, in
particular with her shallower skill curve than other combat classes. We
really want highly skilled Pyros to be visibly more effective than the
average Pyro, and the new features are designed to address that.
Well there you have it, the confirmation that Pyro is actually a girl. You could of possibly guessed this, but at least now there won’t be any speculation.
Walker also went on to say that they wanted to have male/female classes for all the characters in TF2, so let’s cross our fingers in hope.