We have a tortie and an orange tabby and I will say that the female is MUCH, MUCH more vocal than the male....maybe that is something?

Our downstairs neighbor has three black cats. Her youngest one, Jackie, is so, so beautiful! She is lean and petite...I can just picture her being one of Cleopatra's kitties. She isn't very vocal from what I've seen, but I don't see her that often. She is really, really friendly though.