So mine just arrived! I'll be digging in soon enough.
Until then, all I can say is that I can understand those who were hoping for more crunch. I don't mind the amount there seems to be, but I can imagine how someone who had their heart set on a "Complete Warrior" type of handbook being disappointed.
And I can understand the lack of specifics about the Sundering being an issue for some. Personally, my game ignores any of the Spellplague or Abeir altogether, so I don't need a Sundering. The only Realms Shaking Events I use in my game are the Time of Troubles (which happened an unspecified number of years ago, around 25) and the return of the City of Shade. Both of those have played big parts in my campaign.
I guess I'm just a little surprised by the amount of folks who want to know the details of all the changes and so on. I'd think if anyone was into the story that much, they'd read the novels (although it seems those didn't really address everything). As far as the setting stuff goes, I feel like they've left in intentionally vague so that folks are free to make up whatever they want.
I have read the novels. All the Sundering Novels seem to be about the Netherese War, against the back drop of the Sundering, except Ravager which is about the refilling of the Sea of Fallen Stars and Pirates.
Salavator's books after the Sundering appear to be about the Silver Marches, Menz, and Kingdom of Many Arrows.
The last Brimstone Angels book was about Cormyr, but still largely set during the Netherese War.
Spellstorm was a murder mystery set in a mansion filled with archmages.
So we knew the basics of the Sundering, even before the novels were written, tablets of fate being redone, a flood of chosen, repairing the spellplague, the restoration of the weave and lost gods.
But even after the super hyped Sundering Event was done, we had no idea what happened to 80% of the realms, what happened to the planes, ect...
Until SCAG Mulhorand and Unther's return was nothing, but a rumour and that rumour suggested Tymanther was gone.
So there is a sense of frutration with Forgotten Realms fans.
At least with Ashes of the Tyrant, the last of the Brimstone Angels series we should finally get a look at the Unther Tymanther war, and maybe get an idea for what's going on in general in the Old Empires region.