The trauma of dying seems to have restored Sylar to factoy-default. He doesn't remember being Nathan but he doesn't remember being Sylar either. Traumatic amnesia.
Peter is actually reaching out to Angela. Peter is irritated and hurt – Angela is so focused on Nathan, as usual. Like before, those with powers are drawn to each other – this time Peter to Emma. He's lost his previous cool power but has a great if sort-of useless new power. Useless to anyone but Emma, that is. At least – at first blush – turns out that it can be a weapon a kind of sonic weapon.
Seems the creepy vibe we've been getting from Gretchen was right on the money – she really did stalk Claire. She befriended Claire, using Claire's past as an intro, trying to work up a best-friend relationship to build up to a murder-suicide pact. When Claire tries to make new friends, Gretchen goes homicidal. Claire just seems to bring that out in people. Gretchen says it's a crush but it's nothing that benign.
Rebecca is interesting – she's invisible and possibly teleports. Claire was right about Annie not jumping, about the mysteriously appearing suicide note and the equally mysterious moving book. This season has several people who don't have the usual one-power.
Samuel can make the entire carnival disappear! Sylar and Samuel could be a match made in Hell – I really don't like the notion of an amnesiac Sylar being in the hands of someone like Samuel. He's already proven to be ruthless, manipulative and his agenda is still completely unknown.
It's not the first time Hiro's appeared to Peter, this time it's the right thing to do with Peter being a paramedic.