Brian Azzarello has written better things, and Jim Lee is a victim of his own diligence. This series pales in comparison to many of Azzarello's other efforts (check out "Joker" and "100 Bullets" if you don't believe me), and Jim Lee's art is so ubiquitous that one wonders if there was ever a time when he wasn't around.
After thousands of people disappear in an event called "The Vanishing," an event in part triggered by the Man of Steel himself, Superman visits the local priest to deal with his feelings of guilt. The Superman of "For Tomorrow" is both arrogant and condescending, and at no point could I see an advantage to having the Kryptonian protecting us poor humans. If we are going to kill ourselves anyway, and if the presence of Superman merely serves to up the stakes in all of our self-destructive conflicts, then wouldn't we all be better off if he just picked another planet to protect?
I've only read the first volume of "For Tomorrow," and I have no desire to read the second. Even though it might be a commercial success, this series is an aesthetic failure. The plot is weak, the characters are cardboard-thin, and dramatic tension is entirely absent from the series. Yes, giving Superman a credible foe is always going to be tough, but given the array of supervillains available within the DC universe it's not that tough, so I can't give them any points for trying.