As I mentioned in some other thread not long ago, you can add Chris Thomas King to the short list of young-ish black acoustic blues players, along with Corey Harris, Keb Mo, and the not-quite-so-young-anymore Taj Mahal.

(Since Taj is part of my age-group ~ actually a few years older than me ~ I still foolishly think of him as "young.")

Now, are bluesmen folk singers? Whole 'nother discussion.