Basically it's the 'recovery after the fight' chapter. Luffy is asleep, Zoro, Frank, Robin are all there. Sabo comes and checks on Luffy, tells them not to wake him up and when they are all surprised about Luffy having another brother, Sabo tells his story from when he got bombed by the nobles to Dragon saving him to this day.
The sad thing is he lost his memories, only to have them come flooding back when he read the news about Ace (and Whitebeard) dying. So even if he wanted to do something to help, he couldn't because he didn't have his memories.
Anyway, I'm just summarizing the spoilers as it goes into a lot more detail. But yeah, sounds like a really good semi-flashback chapter.
Edit: The crew is at Kyros' house, Kyros, Law, Luffy, Ussop and Bellamy (surprisingly) are all passed out