I've noticed that there seems to be a JUSTICE LEAGUE edition of this series as well as a JLA edition. Can anyone tell me if those are just two different printings of the same book? Or do they have different stories? I'm not sure I've ever seen them both in the same store at the same time so as to be able to compare them side by side. And I can't quite figure it out online either. They have two different covers and release dates it seems.