There are no more episodes until November, so we'll have to wait until then to see how the new revelations are dealt with. I've seen some complaints about the episode, but I liked it. It was a solid, straightforward standalone that had almost no mythology. This allows for time to develop the story and the weird science.
Olivia, Peter, and Walter go to Seattle where people are seeing demons and attacking people. Walter flies back with Keith from Scrubs which is trouble by itself. Peter and Olivia discover that the victims (or killers) had chips in their heads initially designed to help with sleep. They've been turned around to steal dreams as Walter discovers. The doctor is stealing the dreams and seems to be addicted to them. The episode wasn't as much as a whodunit than an episode that showcased science in the Fringe world.
There were several other things going on. Olivia is collecting business cards under order of her new guru Sam Weiss. He tells her to pick random letters and rearrange the letters like an anagram. She forms the message "You're gonna be fine." Before thinking how sweet and touching it is, we must remember that Weiss is affiliated with Massive Dynamic which has its own agenda. I have a feeling he is a means to control Olivia.
Peter tells Olivia that under Walter's guidance, he didn't dream from 8 to 19. 8 is about the age on Peter's headstone and at the end of the episode, we see Peter have a nightmare about getting snatched as a child with Walter in the mirror. Did Walter prevent Peter from dreaming so he wouldn't remember the kidnapping? Did Walter use technology to prevent Peter from dreaming?