There is already a word for people of no specific sex--hermaphrodite, those who have both male and female sexual attributes.

Some animals, snails and slugs, for example, are naturally hermaphrodites. Being a hermaphrodite is not common in humans, but that does not mean they should be considered freaks of nature.

I'm quite happy with finding a new pronoun for those who don't identify with either sex. It's no different than the creation of "Ms." not too long ago.