I liked it. A lot of people are bothered by the ret-con-iness of it, but who cares, it's a good story. Some minor quibbles:
* Wonder Woman's hot pants are ridiculous. It's too bad her costume works so hard to undermine her coolness. Esp. since the other Amazonian is dressed like a kick-ass rock star.
* The rapidly switching omniscient POV was hard to track at times. It switches between Batman, Superman, Wonder Woman and a narrator, often on the same page, often when more than one of those characters is in that panel. Surely there was some better way to convey that information, or at least signify whose head we were in.
But, what else. I guess that's it. This is one of the first times I actually enjoyed the character of Superman. He's so eye-rolly towards Batman. Awesome. That I could use a lot more it.