Shrink somewhat but the difference isn't going away, ever. The problem is that while the costs go up (factor 2.5 from what I heard) the customerbase is constant or even shrinking. That's the reason behind all that 60$/70€ price, DLC, anti-used-sales, tons of special editions, digital distribution, DRM, etc bullshit, a desperate attempt to get revenue growth when the number of customers is not increasing. The HD games are hardly sustainable, the successes are pretty shallow and require wringing money out of the few customers there are while the failures are devastating. That's more of a philosophical difference than an actual hardware issue though, the industry has fallen into a blockbuster mentality that is completely out of touch with what people really want (do HD graphics really increase our enjoyment of the game 2.5 fold?).