In a nutshell, Zoe’s Tale is The Last Colony told from Zoe’s point of view.
It definitely has a different feel to it than the rest of the Old Man’s War books, matching the idea that it was written by a teenage girl (having never been one, I can’t guarantee the accuracy, but it worked for me).
After John’s story in Old Man's War and Jane’s (to some extent) in The Ghost Brigades, this time around we get both of them. They’re together now and raising Zoë (how’s that for a complicated family), when they’re tapped to head an entirely new colony planet Roanoke–with the first city named Croatoan. Also… why would they even agree to that?
I mean… come on. Either no one knows the history behind the names–in which case why in the world would they be using them–or they do–in which case why in the world would you choose that to name your new colony. Granted, they turn out to want it to be lost, but still. It’s a bit annoying.