I just finished reading it yesterday, and I thought the same thing. While part of me does want solid explanations (which we may get some of), another part really liked it like this.
Some points in the story:
Valor in the Phantom Zone. I'm not completely clear on the whole Valor/Mon-El/M'Onel thing, but is this Valor the one Superboy/Kon-El put in a 'Phantom Zone' in Superboy #20-something?
Supes 'remembering' Krypto. I didn't read Superman #166, so is Clark referring to getting memories there? Or was he remembering memories (heh) just being on this Krypton? I guess we'll have to wait...
The current Kandor being essentially a 'concentration camp' for non-Kryptonians, again tying it back to Krypton. This can lead to Superman feeling a responsibility to restoring it, since his people gathered them there in the first place.
The ancient Kryptonians being electromagnetic. Think about this: Those tombs were in the remains of Kandor. The implied reason for Superman turning into energy was being in the dimensional border of Kandor. Hmm... Also, the meteor that Supes found was 'sent' by them. I wonder where Mark Schultz is going with this?
Will Supes change the Jor-El and Lara Fortress statues?
At the end, Lara says that Jor-El is the new President of the Council. Doesn't this change it, because the rest of the Council *would* most likely believe him when he says Krypton is doomed? I guess this means that this Krypton *is* an idealized dream? Hmm...