I think, first and foremost, the movie should not look fake. No obvious green screen stuff. You can tell that this is the case in Miller/Rodriguez "Sin City", "300" and even "Sucker Punch", but it WORKS. I just don't think the same technique could work for Superman.
Nolan's movies on the other hand look real. Even Inception was, in my words, the most realistic unreal movie. But the color palette in most of his movies is bleak. Cold. Anti-Supermanish.
"Dawn of the Dead" and "Watchmen" were good in their style. Now, I know that slow-mo is to Snyder what explosions are to Michael Bay, but I am sure Nolan can convince him to keep it to a minimum. Still, "Superman Returns" and even "Inception" had many slow-mo sequences. So, they need to find a middle ground, which I am optimistic, they will.