The Pirates are peddling Mike Gonzalez. The most common rumors are Coco Crisp and Melky Cabrera.
I think Melky will be a solid but not great major league OF. The New York Yankees fan hype machine thinks more of Melky than most. I'd be shocked to see him crack a 900 OPS at his peak, and that's probably what he'd need to do to be a standout OF long term. I lean toward Melky over Coco at this point, though Coco might have a better year next year than Melky.