With all my hate of Jason Aaron, I'm just glad he's writing the Celestials like they should be written... until he doesn't of course.
Story is crap though. It reads like a youth mystery novel. I predict Odin joins with the normal Celestials or they let him go, and they replicate the energy of the Dark Celestials which is for whatever reason also their weakness to defeat them. Or they infect them with that Horde or something.
Of course Aaron might just make Odin lash out and defeat the Celestials in the flashback and Binary might just absorb and redirect a big blast and kill them all. This is Aaron afterall.