Well language like Kyeruu's is only on the net really, people just don't talk like that in the real world, for the most part.

As for ebonics, like Grav said, most black people (and some white people) are quite capable at speaking normal english but chose not too. They have that freedom in America.

EDIT: Just an added note, I'm more worried about hispanics myself. More and more come here every day, and more and more Americans are forced to learn spanish so businesses can get that consumer base. Before long, everyone in America will speak spanish because it will be majority hispanic(if it isn't already, I don't know the numbers all that well.)