Overall, I think it was pretty good, but no where near as good as WW or GL.
Theres a lot of great stuff in the movie, and technically, based on the concept of the movie, could be in continuity with the DCAU, just a different world. It was very similar to JL and JLU, which I think actually worked to its benifit, but also felt like its own thing.
Where I think the movie falls apart is the ending. The OwlMan vs Batman scene was great, but the rest of the ending seemed to wrap up really abruptly and without a real payoff. I also found the whole bad flash turning noble thing to be corny and out of character.
I just dont think the whole Crime Syndicate working with the JL thing was handled particularly well. It felt rushed and under whelming, and I think hurt the movie overall, as well as the whole "I brought the Marines" part.
It was good, w/ great parts, but falls far short of WW and GL, but was a massive improvement over "Public Enemies", imo.
I want to believe that the dead are not lost to us, that they speak to us, as part of something greater than us, greater than any alien force. And if you and I are powerless now, I want to believe that if we listen to it speak, it can give us the power to save ourselves.