It's actually quite fortunate Luke hasn't been seen with it, as I believe the Wrecker can influence and control anyone holding his crowbar...god that sounds wrong.
I would say that Wolverine can cut Luke Cage's skin. Luke has wavered in power over the years, originally he was probably around class 5 with steel hard skin. He was bulletproof, but it stung like hell to get shot. During Heroes for Hire (Ostrander era with the big team) I believe his skin was likened to diamond and whatnot. At one point he underwent the strengthening process again, so that boosted his powers to some degree.