There's an interesting e-journal article from the Council on Foundations about board diversity.
True to its source, the focus is Foundation Boards but I think the "debate" is good for the whole nonprofit sector. Sadly, the article's title is very misleading: Mission or Board Focused?
I say misleading because Foundations and nonprofits are simply "mission focused" while boards and their interests affect what the mission is and how that mission is carried out. That being said, the actual subject of the article is how a board achieves diversity. And the "debate" is much more about how planned or intentional a board needs to be about being diverse. That subject is most interesting while flying somewhat in the face of planners like me.
Anyway, check-it out. I think this a worthy conversation on a much broader level.