Al Sharpton's spokeswoman confirms this Examiner.com report that the Rev is voting for Charles Barron, not fellow Democrat Andrew Cuomo.
"He intends to vote for Barron, but he's not endorsing anybody," Sharpton's spokeswoman told me. The difference between publicly announcing who you'll vote for and who you'll endorse is fuzzy. But one thing is clear: Sharpton hasn't raised his voice in opposition of Cuomo, which, in New York, is like an endorsement too.
Attached above is a press release from Barron's campaign, which has its own description of Sharpton's role.