Sorry; I didn't have an answer for your question, and didn't want to look at even a non-spoiler thread until I saw it.
Now that I have, I liked it. There are a few wonderful moments in it, and no really awful ones that I can recall. I got to see some of my favorite heroes up on the screen.
I went to see it without ever seeing Superman vs Batman, and never missed it. I probably enjoyed the movie *more* because I didn't see the movie everyone says is disappointing.
I figure if there was a novelisation Amazon would have it. My search "Justice League novelisation" found a couple of Justice League coffee table books, but not a novelisation.
...A belated thank you to both Rob and Luke.
Now, since I have finally seen " JL " to-day, I cannot find the with-spoilers thread for it. Could someone please bump it up for me?
Here's a link to it.