I'm afraid Lana's death would be too much to hope for as much as I'd love for that to happen. I'm still anticipating some sort of breakup for two reasons. One, Clark is clearly destined for Lois from all canon. When Clark said he couldn't imagine loving anyone but Lana for the rest of his life, who drives up a second later? Lois, of course. It's interesting how when Clark says that, his eyes drift off slightly to the side to see Lois's car pulling up.
The second reason is that they've been playing off of the chemistry between Lana and Lex. I think they're actually trying to set those two up. It's already been outright stated that Lex loves Lana. We just don't know whether Lana has any feelings for Lex.
Oh, did I state my third reason already? I'm just not that lucky for Lana to be the one to be killed?
My opinion is that they'll kill off Jonathan. By old canon (pre-crisis), he's supposed to die anyway before Clark reaches adulthood. Plus he'd been weakened by that whole deal with Jor-El. He'll win the election, of course, but will die right after he finds out.
Of course with my luck, it'll be Chloe, my favorite character.
The thing is, I'd be happy with Lana dying, if this wouldn't leave a big gap in the current Smallville-storyline. Looking at Clark's current friendships, what's there to build a plot upon? Chloe is the zealous reporter for The Planet and rarely present in another scene/situation, Lois is mainly interacting with Clark's parents and Lex was for a long time leaning towards the dark side.
