Eh, at this point I look at FR like I do with the X men movies. They are all over the place and forget trying to find a single thread of continuity. But that's OK. It seems clear to me they are throwing things from almost every setting into the FR universe and going with it. I honestly think there aren't that many players who are getting hung up on the continuity breaks, because I feel safe is saying most people want their PCs to be the heroes and mold the game world, and all those NPCs are just there to facilitate that. In that case, continuity isn't all that important between editions. I mean, are there really that many people who are really upset that FR now includes Grayhawk deities? Maybe a handful, but that's about it. From what I've seen anyway, anecdotal evidence and all that.
For me, the campaign setting was 95% just the maps anyway. I always modified NPCs and stories to match what my players were doing in the game, drag and dropping all kind of things into the campaign setting.