Anything in particular Blondes?? I can give you a general overview from my point of view, but whether I am right I have no idea! I am loving Fringe at the moment but think a lot of it is going straight over my head!
So, Jones kidnapped Olivia and tortured Nina in an effort to trigger Olivia's cortexiphan induced powers. Olivia seems to be able to recall both Peter Olivia's (Polivia?) memories as well her ones of being brought up with Nina. Turns out this Nina is the alternate one and is working with Jones, whilst Broyles and co are interrogating the real Nina. Peter is brought in and Olivia uses her powers not only to turn on the lights in the box but to help them escape. Jones and AlterNina cross over back to the other side after Jones seemingly caught a bullet when Olivia shot him 
Peter meanwhile had gone into the Observer's mind where we learnt his codename was September and he was from one possible future of the human race who had developed the technology/power to travel all the way through/inside/outside of time to learn about their origins. Peter learns that he had a son with Fauxlivia, that it was a relationship that was never meant to happen, and Henry was someone who was never meant to exist. We learn that September thinks Peter is incredibly important, that he was always meant to live but it was he who distracted Walternate from finding the cure to save him which is why he interfered later so that Walter would save him. He stressed how important it was the Peter ends up with the original Olivia which leads to Peter once again rejecting this Olivia, saying he has to go home.
However... I definitely think that this is the original Olivia. When they were trying to search through the videotape for old underlying footage, Walter compared it to a 'palimpsest' (SP?), a scraped manuscript, where what was underneath can sometimes bleed through. This seems to be a metaphor for what is happening to Olivia, that her old original memories are beginning to bleed through her new persona. Perhaps it is happening to her because of the cortexiphan that Jones and AlterNina have been secretly injecting her with, and that's why it is not happening with anyone else?
I'm sure I have missed loads of important things so hopefully someone else can fill us in on the rest. Is AnnieK still around??