There are certain classes that have been 'traditionally' one or the other through out the fanstasy realm, ie. look through 'most' (and I use that term very loosly) books, games, movies, etc. and you will find the 'healer' class being female. The brawny, fighter classes are usually male, and the other classes are a mix of either. Spellcasters can be either, though wizards are generally male in fantasy as female spellcasters are most often sorceresses.
Then there's the female butt thing....thats got merit.
And the WF female voice in DDO is just hilarious...