A couple points:
1.) I think Al Sharpton is right that there is virtually nothing to be gained--and a lot to be lost--by trumpeting a black agenda. The fact that African-American leaders are, in the main, not doing this, from my perspective, is really smart and perceptive. People are already skittish about health care. It makes very little political sense--or even logical sense--for Obama to aid Glenn Beck in his crusade to cast health care reform as reparations.
2.) I don't know what a "black agenda" is. I can think of very few policies which I would say are good for black people, but aren't good for most of America. I think Tavis would agree. (His site says "a black agenda is an American agenda." But that only raises another question: why would we calling it a "black agenda?" Surely changing the way we approach incarceration would help black men, but were there no black men in this country, we still would do well to think about how we incarcerate people.
I'm at a loss to see what we gain by simplistically racializing problems that may well have a racial component, but aren't wholly, and in many cases even mainly, racial problems. To be clear that component should be called out. But it seems you implicitly alienate allies when you claim that broad problems are the property of specific communities.
Moreover, you do the work of your adversaries. Nothing would please them more than for America to think of incarceration as a "black problem" to be addressed by a "black agenda." People hear "black issue" and they feel relieved--"Oh well, it ain't my problem." Except that it is. And we should make them aware that it is.