I don't know from "writing for the trades," but the way the first issue of Justice League is put together story-wise makes a lot of sense to me. Introducing these characters a couple at a time and establishing how their personalities and abilities complement and irritate one another, how they differ in their approaches and their self-images, how they help one another out and get in each other's way, seems to me a better way to draw someone into being interested in following them than throwing six characters at a new reader right away such that about the only thing the writer can do is line 'em up for a roll-call and a little supposed-to-be-clever banter while they fight something.
The idea that Batman and GL are naturally antipathetic to one another has struck me as really perceptive since it was first introduced, and I think some of the reasons it's so are laid out pretty plainly in this encounter.