Mostly fantastic, with just one or two fumbles. The title tells you exactly what you're going to get: the New 52 version of the JLA's origin story, this time including Cyborg. I'm very happy with this addition. I love Cyborg, and his origin is very nicely told here. I don't really have any complaints about the story itself, and most of the characters are well written. Superman in particular shocked me by being pretty awesome, in a way that totally suits his character as I know it. I'm not sure I remember ever being quite so wowed by him before.
The only real problem here is Wonder Woman. Her dialog is painfully flat. Johns seems to have been going for a warrior awed by her surroundings, but she instead sounds almost childlike. I was also irritated by how casually she waved her sword around in normal situations. Her Amazon sisters would be more than a little annoyed to see her using it to point at things and people for emphasis. And I like Lee's art, for the most part, but I can't stand this version of her costume. Apparently, one of Wonder Woman's superpowers is avoiding wardrobe malfunctions.
Wonder Woman aside, this is a really enjoyable book. And frankly, I'm almost used to writers misfiring when they try to write her. This is better than what Miller's done with her, at least.