Even if you aren't using the Forgotten Realms, they've provided advice on how to use most of the new character options. The character options are:
Subraces
Gray Dwarves/Duergar
Ghostwise Halflings
Deep Gnome/Svirfneblin - You can get this for free from the Elemental Evil Player's Companion though
Half-Elf variants - Replace your two bonus skills with certain elf features depending on subrace (including drow and aquatic)
Tiefling variants - For tieflings that aren't all about Asmodeus--basically for 2e-3e tieflings
Subclasses
Battlerager (Barbarian) - Dwarf. Includes entry for new type of armor
Totem Warrior - Adds two new totems to choose from
Arcana Domain (Cleric) - Actually pretty awesome
Purple Dragon Knight (Fighter) - For non-Forgotten Realms campaigns they suggest "Banneret" as the name. Inspirational leader type.
Long Death (Monk) - Evilish/necrotic feeling monks
Sun Soul (Monk) - Goodish/radiant feeling monks
Oath of the Crown (Paladin) - Take the traditional paladin, split it in two, make one half lean more towards good (Oath of Devotion from PHB) and one half lean more towards law (that's the new Oath of the Crown).
Mastermind (Rogue) - The "social rogue." I don't mean social character that happens to be a rogue. I mean if you took a rogue and made a social type, this is that.
Swashbuckler (Rogue) - Cool concept. Some conceptual interaction problems with limited rogue weapon proficiencies, but other than that it's neat.
Storm (Sorcerer) - Coolest sorcerer in the game, IMO.
Undying (Warlock) - Patron is either immortal or undead, you have powers of life and death
Bladesinging (Wizard) - Elf or half-elf, warrior mage
Cantrips
Booming Blade - Adds to melee weapon damage and provides some control
Green-Flame Blade - Adds to melee weapon damage, and deals damage to secondary target
Lightning Lure - Lighting whip that pulls
Sword Burst - Very similar to thunderclap from EE, but different save and damage type
Backgrounds
(Backgrounds hardly count as crunch, because the rules give you explicit permission to build your own by combining any 2 skills, any two tools/language, any equipment package, and any feature--but they do give you new features to choose from, so I'm including them for completeness)
City Watch, Clan Crafter, Cloistered Scholar, Courtier, Faction Agent, Far Traveler, Inheritor, Knight of the Order, Mercenary Veteran, Urban Bounty Hunger, Uthgardt Tribe Member, Waterdhavian Noble
I got the book because I wanted that stuff. Green-flame blade itself is an essential part of my games because it allows any character to get a scaling melee attack with a feat (like ranged cantrips allow anyone to gain a scaling ranged attack). You can download that particular cantrip in a free preview they put up.
Other information that isn't specifically Forgotten Realms is the racial pantheons for Dwarves, Elves, Drow, Halflings, Gnomes, and Orcs (these are traditionally shared amongst multiple D&D worlds and settings).
Pretty much everything else in there (so 80%+) is Forgotten Realms specific. It also is specific to the 5e Forgotten Realms, so if you are playing in an earlier era (as I am) and care about continuity, you can get some value out of it, but you have to go over it with a fine toothed comb. They tried to make the 5e FR feel mostly like 2e-3e era, with a dash of 4e material, and it is set over 100 years in the future from 3e.
The book has some nice art in it.
I wanted it primarily for the crunch (even though I'm philosophically opposed to crunch bloat...). All of it is useful for non-FR D&D campaigns. You could easily drop it into Greyhawk or your homebrew world, and they even give suggestions for how at the end of the book. (The little Ghostwise halfling sidebar is the only piece of crunch that is Forgotten Realms specific.) I'd get the book just for material.
Most of the setting information is of limited usefulness to me because when I play Forgotten Realms it's set in an earlier era, but I like a lot of the material on the Forgotten Realms deities.
Hopefully that can help you decide whether it works for you.
[EDIT - I see I was beaten to the post. Well I spent a while on this so I'll leave it up anyway.]
