You can tell who here are comic fans, because so many people are suggesting stupid comic style stuff, like just ignoring certain plot twists from the other movie, having half-reboots, with some of the same actors, but not the others. Geez, how pointlessly convoluted is that? I mean really people, keep Routh but ignore the kid? WHAT?? That's the dumbest thing I've ever heard. It's the sort of nonsense that comic readers dig but everyone else just stares at with a glazed look in their eyes, then walks away. What's the f'ing point of being so obtuse about the whole thing?
Anyways it should be a direct sequel, or a total reboot, with nothing in between. My personal preference reboot, and I'm very much over the Donner-started series. I liked them in their time, but I'm over it. And I believe most of the younger generation doesn't see those movies as the end-all-be-all of Superman that can never be replicated. In fact, I'm not surprised if the majority of people 20 and under have NEVER EVEN SEEN it.
However, if they want Routh it should be a sequel, plain and simple. That's fine with me too.