Oh man, I don't know if I can wait 3 months to see what happens. That was a pretty intense cliffhanger, although I'd be inclined to agree with Dan-el in that the conflict will, ofr the most part, be resolved in the first episode of next season, with maybe some lingering ramifications to that resolution defining the rest of the season (example: resolution of Kryptonian arrival leading to Clark losing his powers and Jonathan Kent's death).
Anyways, it looks like the fates of Martha, Lois, Lionel, Chloe, Clark, and Lex are all pretty much up in the air. We can all pretty much assume, I'd think, that Clark will find a way out of the Phantom Zone pretty quickly--possibly with the help of Jor-El and/or Lex--and that Lex will eventually find his way out as well, although when is a question there. Martha and Lois, obviously, will make it. That said, I can't shake the feeling that now would almost be too convenient a time to off both Chloe and Lionel together, considering that both know Clark's secret. That would be a huge drag, though. They're both great characters, and without them I could see the series growing very stale very quickly.