I slightly hate myself for not figuring this out.
So we all know Fringe ended its first season by showing us the existence of a parallel universe, one where William Bell's apparently been hiding, in a still-existent World Trade Center. While it's understandable that we'd see characters cross over from what they call "over here" to what they call "over there" (as Livy just did), I didn't realize that the crew can take that aspect up and use it to confuse us.
"Which reality are we in when season 2 begins?" floated the folks at TVGuide.com. They're saying it's an important question in the season premiere, and of course, that goes without saying that it'll be a question throughout the entire season. In other words, some scenes will be set over here, and some scenes will be set over there, and we won't be told which universe we are in. Sure, we'll notice that a few details are there--if we see the WTC in the New York skyline, it means we're over there--but for the most part, I think it'll be an important twist to how we watch the show a couple of weeks from today.
Maybe something like Livy's dreams last season? Remember when she saw two burnt bodies when everybody else saw only one? But that's a warning, yes, so I'm guessing that doesn't count. I'm imagining a situation when, say, the parallel version of Walter dies but we'll initially think it's the actual Walter. Someone floated that idea in one of my previous write-ups, and now it makes perfect sense. (DilutedBetter, you're a genius.)
So that possibly means that a parallel version of Peter and Olivia will kiss, as most of you want to see. (Disclaimer: I don't.) What I'm trying to say is, as we've all seen in the first season, what happens there will affect what happens here, and whatever happens to the parallels could mean life or death for the actuals (to borrow a Dollhouse term).
I'm looking again at the photos from the Fringe season premiere, and now I'm thinking: is the car accident in a parallel universe? Oh, wait, it can't be, since parallel Peter is playing actual Peter, or so we all think. Unless--and this is a crazy idea--it turns out Walter took something from parallel Peter and made himself a brand new actual Peter? Okay, that is crazy.