Is it really a quantum leap tho? Like Jacko said he has always had this kind of power. What has changed is his approach at the plate and contact skills. Those are not the areas in hitting that get better with PED use. His power progression along his career hasn't spiked, he's just gotten more AB's. Dude could totally be juicing, that's just how it is in this new era of sports. But there's nothing that jumps out and makes me thing "he's on something".
He also a week or two back came out and took a stance against PED use. So if he is using he's got a huge set of balls to put himself up on that pedestal and be using.
Whatever, it's great to watch(albeit I wish it wasn't for a division rival) and I hope he breaks Bonds record as Bonds is a Giant douche(not because of PED use, he's just seems like a real douche).