Here’s “Proof” that Scarlett Johansson and her Black Dahlia costar Josh Hartnett are, indeed, still a couple. They were together in New York this weekend after what seemed like a long separation. Scarlett has been seen out and about having fun with her girlfriends, sparking rumors of a bustup. It’s no secret that she loves the limelight WAY more than Josh does, but they ARE an appealing pair. If Josh is smart he’ll let her get that party hunger out of her system.