Wizards of the Coast has released the Forgotten Realms Campaign Guide. There's a review at RPG.net that is less than glowing. Judging from the material mentioned in that review, I think my opinion would be even worse.
The 4e staples have been introduced: Dragonborn, Tieflings, the Shadowfell, Elemental Chaos, and so forth. To accomplish that they killed Mystra and had the world plunged into a hundred years of magical chaos. The reviewer gets the detail about the Great Wheel wrong (it existed in the Realms in 2nd edition and earlier, but Wizards changed that when they updated the Realms for 3e), but apparently it's been smashed up and somehow became the Chaos and Shadowfell and Feywild and stuff. Gods have been randomly removed or redefined as something that's not really a god.
Other weird things have been done. The ancient empire of Netheril, which destroyed itself in a magical holocaust centuries past, is suddenly back. There's no such thing as Maztica, which has instead been replaced by something called Returned Abeir: a confused fragment of the plane of the gods mixed up with bits of the Elemental Chaos, fallen to the planet. Apparently there's a major metropolis and a lot of wilderness on it? I don't know, but I'm not buying it.
I mean, I'm really not buying it, with money. Let's try a thought experiment: There's this setting just put out for 4th edition D&D. (Let's assume that I'm playing 4e at all.) The book presents a post-apocalyptic setting that neatly mixes up the fiction elements of the main 4e book in a novel way. There are countries swarming with undead, mystical plagues, magic-warped mutants, a mess of elemental and godling stuff going on across the sea, and the darkness and decay that a century of apocalypse brings. Now let's call it The Ravaged Domains Campaign Guide. It sounds pretty cool, but it's not the Forgotten Realms.
I do think there are some interesting ideas in there. I like the elements that have been put into this stew, and I might be tempted to get it just to scoop out and repurpose the bits I like. On the other hand, I have lots of raw material lying around as it is, and buying it would be sending Wizards of the Coast the wrong message. The right message is: I do not approve of this new Realms. I'll be keeping my 2nd edition boxed set near at hand, thank you.