I think it's long enough for at least biyearly announcements for what's coming over the next 6 months.
Anyways given the Domains of Delight are supposed to get a dmsguild guide, I'm not as certain it's one of the new settings, intact it seems more like it was originally intended to be a new setting book, but they converted it into an adventure, but didn't want the how to make your own Domain of Delight chapter that the book didn't need now to go to waste, so they turned it into a PDF. I think as far as AL will be concerned the Domains of Delight will count as a part of the Forgotten Realms, even though it has more in common with Ravenloft.