Much like Charlie's heading up of the slushbombing of F&SF, I suspect that if this is not headed by a "writer of color", it would get the same sort of hairy eyeball.
It's an interesting idea. I'm all for mentoring writers, but I think there are a whole lot of factors that would need to be examined. Like, reasons why there aren't more "writers of color" writing in the genre. There's probably some "don't see the authors already there, so we're not welcome" going on. Could that be resolved by more pushing or holding up of the authors that *are* there? (Octavia Butler, Steven Barnes, Nalo Hopkinson, etc. for instance.) Don't know, maybe.
Much like more positive representation in the media, it'd be great to have it in genre fiction, too. I'm just not sure that this sort of mentorship would make it happen. It's an interesting thought, though.
As a side not, I'd dearly love a different phrase. "Writers of color", anything "of color" sits uncomfortably with me.