James has a very different style than we've seen on JLA for a while. He's more interested in character building that just having people fight each other. So there's a lot more thought-captions and internal narratives that you'd see in other books. And if you read those captions, you'll see that the characters he's writing about are growing exponentially. He's made Congorilla and Mikaal Tomas into more three-dimensional characters than they've likely ever been. He's done a good job of showing that the former Teen Titans deserve a place on the JLA, as opposed to merely being interim title holders.
His first arc brought a good close to the characters he used in CFJ, with an obligatory Blackest Night crossover folded in. His JLA JSA crossover, "Dark Things" gave a proper return to Jade, as opposed to her one-panel return in BN. And all throughout he's been building up the foundation to his current arc, Omega Man. He's given us a look at bunches of classic DC characters, in a series of flashbacks designed to set up the existence of a powerful device. He's come up with a solid use and explanation for Doctor Impossible, a character introduced in Meltzer's run on the book, one who almost every writer since has used and tried to explain, and failed. He's been given permission to use the Multiverse, something that had been allegedly locked down until Morrison gets his Multiversity mini-series done. In the most recent issues, we've discovered that these "dark gods" have been trying to resurrect Darkseid, only to end up bringing into existence the mysterious Omega Man. In short, he's been writing a series of pretty cosmic-level threats, exactly the kind of things the JLA should be fighting. And doing it well. Add in a few done-in-one semi-solo stories that further build up the character of the characters and you've got a pretty solid run to date.
So why is he still catching crap from the readers?
I think Cry for Justice is where the honeymoon ended. That CFJ was a divisive storyline is a grand understatement. And perhaps of that, his run on JLA has been met with many brickbats. "He doesn't have any of the big guns on the team" (like that's the first time that's ever happened) "the roster is changing too much" (Again, lots of precedence, and he's got it to a stable point now, and considering the rasher of shit the DCU has gone through in the last year, it's no surprise things have been in a tizzy) and lots more.
Sometimes I get the impression that fans are angry at him that he won't just suck under and give them what they want (i.e. more Jack Knight) and view everything else he does as lacking. They come off sounding like a spoiled child at Christmas saying " I don't CARE that you got me a little battery-powered car that I can ride around in, I WANTED a pony".
Also, ever since the rumors (persistent but so far very without merit) of a Johns/Lee helmed JLA, some readers have been viewing everything else as a long lame-duck session that they must suffer through. It's bad enough when that happens to a book when a team change is actually announced; current events JLA are being looked past for something that doesn't even exist.
So readers are in a funk, and are reading the book with a chip on their shoulder. And so every plot-point that they don't like or understand are painted as colossal failures. Case in point; in the cliffhanger in the latest issue, The Omega Man transforms Supergirl into the black-costumed "Dark Supergirl" that we saw in the early issues of her solo title, the ones that had a lot of readers scratching their heads. Readers quickly clamored that Dark Supergirl had been expunged from continuity by Sterling Gates, and for James to bring it back means that either A) he didn't know it had been removed, B) He knew, and didn't care, or C) some other explanation that can end with "and so he sucks".
Depressingly few people seem to be considering D) He knows what he's doing and has a story in mind.
When asked, Sterling Gates has said that James does indeed have a plan in mind for this story ("and it's pretty cool"), from which I infer that he didn't "forget" anything. Considering the pair worked together for a year on Superman, I'm willing to bet that's true. But since the readers have already made their choice, any data that comes along MUST go into the negative pile, or they run the risk of being proven wrong.
It's a mindset that I've come to call "The Presumption of Error". If the reader has already decided (for whatever reason) that they don't like the writer of a story, they assume that any change they make to continuity is due to gross incompetence or disrespect, and not that they may have a good story planned.
In some cases, it's hard to tell if a change is an error or not, but if the end result is a good story, it's usually not too big an issue. The very creation of Wonder Girl was the result of a mistake; Bob Haney mistakenly read a series of "impossible tales" (AKA "Imaginary stories") featuring Wonder Girl as if they were a separate character, and added her to the Teen Titans. Nobody's demanding to go back and write off all those stories because he got the continuity wrong. (They've gone to great lengths to try to explain her past, but that, to say the least, is another story.)
In Justice league, Generation Lost, Judd Winick has been delivering a solid story, one far better than a lot of people thought him capable of; myself included. So when little "oopsies" started appearing in the narrative, the staunch anti-Winick crowd declared the story an abject failure; if he can't get little details like this right, how could he possibly write a good story?
One of Captain Atom's "powers" is that if he absorbs too much energy, he jumps forward in time. It's the basis of his DC Post-Crisis origin. But in JL:GL, Atom has now been able to travel BACK in time to the point of his departure, once his body had processed the energy. Now I've yet to find precedent for this new ability, unless it's an extrapolation of the dimension-hop from the Wildstorm "Armageddon" mini, which was pretty damn good. So it appears to be new. But again, in the eyes of those who presume error, he's either just unaware of how Atom's powers work, or he doesn't care. He's been quoted in interviews saying that he doesn't worry all that much about the details when telling a story. I understand what he means, and he's right - one should never let continuity get in the way of a good story. Making Atom now be able to only temporarily jump in time isn't too big a change, unless he tries to claim he could do it all along, in which case it would rather invalidate his whole origin. So yes, it's a change. At the moment it's made, it may sting a little, but in the fullness of time, it will either become canon (hey, Superman only used to leap an eighth of a mile once) or it will be ignored or re-written by someone else. Often, both.
Also in the latest issue, Power Girl was able to be taken down by Kryptonite, possibly artificial Kryptonite. Small problem; PeeGee is from Earth-Two, the pre-Crisis Earth-Two to boot; Earth-zero/New Earth Green-K doesn't affect her, or at least not to the degree it would (our) Superman. So while I recognized that and assumed that it was somehow successfully synthesized E-Two Green-K ( a challenging prospect but hey, they had 120 years to perfect it, so who knows), the haters just used it as another log for the Winickaust.
View continuity as a foundation garment and not a strait-jacket. It's supposed to support you without restricting your movements. Don't let the length of Batman's cape keep you from reading a great story.
David's Law says "If the reader or viewer wants a particular ending or event to happen, they will accept any damn fool thing you have to do to give it to them" Bartilucci's Inverse to David's Law states "If a reader does NOT like the ending you have written, they will latch onto any "error" you made in narrative or continuity to prove it's invalid". Alas, far too many readers nowadays live by the latter and not the former.
It is entirely possible for a writer you've never liked to knock it out of the park. But if you insist on spinning the stats so it didn't count, or finding ways to find fault with every story based solely on your dislike of the writer and their past performance, you run the risk of cheating yourself out of some great stories.