I know a lot of people are going to disagree with me here, but I absolutely loved when 4kids dubbed the PKMN Chronicles special: The legend of Raikou--and formally changed Atilla's gender from male (in the original JP version) to female (for the dub).
I thank you 4kids, for saving the dubbed audience, the hardship of character gender confusion. I think Viz needs to learn from this.
Speaking of the Pokemon anime, the gang's pokemon are constantly being debated as to what gender they each belong too. I remember when everyone discovered Aipom was a female--the big shock on everyone's face continues to haunt me today.
Anyway, what I dislike hearing the most is when the dubbing writers and/or the plot writers address a pokemon as an "it" instead of a "he" or "she". In my opinion, the word "it" should only be used to address exceptional pokemon (like legendaries, etc.), since this type of dialogue discriminates against pokemon and only serve to mislead the viewer that pokemon are only tools and not living beings.