From a linguistic standpoint, it's pretty interesting. It's a form of Pidgin, a conglomeration of different languages meant to be used by a group.
African/Carribbean language has been changing American English for probably more than 400 years. Words like "okay," "banana," "jive," and probably 80 percent of the "cool" language of any given generation can be traced to our African American neighbors. Twain used it in
Huckleberry Finn.
There's a standard of English that should be universal, but let's never forget that English changes every day. It pisses me off that "friend" has turned into a verb in the last two years, thanks to Facebook, for example. Five years ago, who would have "friended" somebody?
Weird thing is some blacks speak that way among themselves but speak normally when talking to white people. I've seen it more than a few times at fast food places.
Although it's much more pronounced with black people, we all do that to some extent. I bet you talk to your spouse differently than you talk to your boss. Or your minister differently than your children.
I'm trying not to turn this into a vesta-style post...I hope you guys see where I'm coming from. Linguistics is a bit of a hobby of mine. And it's summer, so I have no students to bore with this bs.