It definitely would be a good thing but from what I hear, most of the better pre-home-video-release pirate releases actually come from people working in cinemas, so if the DCPs can be broken, I'm afraid they probably will be, very soon after they hit cinemas. But maybe they'll come up with some additional protection to keep that from happening. I think it would be a tragedy, especially for smaller films - not many people are willing to watch movies recorded in a cinema with a shaky camera, so the losses from that, while probably not negligible, are not huge and by the time the film hits BD, it's usually earned quite a bit but if a good quality copy made its way to the internet this early, it could really hit the profits badly. Just a few years ago there was a case of this Czech film, which was expected to be quite successful (within the constraints of such a small market anyway) but it leaked on-line in DVD quality and it bombed in the box office, most likely because of that.

As to the screenshots, I only need my eyes to tell me they are not identical - they evidently come from the same original digital source but the WOWOW definitely has more compression artifacts.