So from this May 3rd post, “Four Reasons Krypton Doesn't Blow Up in the new Superman Movie 'Man of Steel,'” it looks like alternate theory 2:2 is the correct one (“Or he's got a spaceship that's roaming the cosmos”). It also means Entertainment Weekly was wrong in its summer movie guide description of “Man of Steel.” Or the above doo-dad is wrong. We'll find out soon enough.
If the above is right? The plot is taking shape. Kal-El searches for himself on Earth, hides his true nature because people here would freak, and doesn't truly emerge until this threat, Kryptonians taking over Earth, arrives. Cue: battle. But I guess we already knew this.
BTW: That's the best Shannon-as-Zod photo they could come up with? It looks like someone just told him his dog ran away.