The info:
I'am trying to compile the answers here by those who have new information. The answers do not represent me in anyway I'am just passing on the information.
Q: Name all the subclasses (submitted by me)
A:
Not really interested in spoiling all of the specifics, but here's what I noticed to be new at first glance:
Races:
Gray Dwaves (Duergar)
Ghostwise Halflings
Deep Gnomes (Svirfneblin) -- also provides a new feat "Svirfneblin Magic" (same as EE)
Half-Elf Variants
Tiefling Variants
Classes (only new class options, not new classes):
Barbarian - Path of the Battlerager, new Totem Spirits
Bard - New musical instruments
Cleric - Arcana Domain
Fighter - Purple Dragon Knight
Monk - Way of the Long Death, Way of the Sun Soul
Paladin - Oath of the Crown
Ranger - Several paragraphs that amount to nothing
Rogue - Mastermind Swashbuckler
Sorcerer - Storm Sorcery
Warlock - The Undying
Wizard - Bladesinging
New cantrips for sorcerers, warlocks, and wizards
Booming blade, green-flame blade, lightning lure, sword burst.
Backgrounds:
City Watch
Clan Crafter
Cloistered Scholar
Courtier
Faction Agent
Far Traveler
Inheritor
Knight of the Order
Mercenary Veteran
Urban Bounty Hunter
Uthgardt Tribe Member
Waterdhavian Noble
This only covers about 50 pages of the almost 160 page book. There's a TON of info on the Sword Coast itself. I'm sure DMs who already have the book are salivating at the moment.
Q: No Bard, Ranger or Druid subclasses?
A: There are new bard colleges. I only listed non-flavor changes (in my opinion at least each one is paired with an existing class option so nothing new in terms of mechanics.
-Q2: Wait WHAT? So the Bard Colleges AND Druid Circles don't list fully new subclasses that offer new mechanics to that class? And no "spell-less" Ranger variant or anything?
-A2: Correct on all accounts.
Q: Monk Subclasses specifics
A: Sun Soul gives the monk methods of dealing radiant damage. Burning hands makes an appearance as well.It seems almost too obvious, but all of the Long Death abilities are triggered by death in some way - either yours or an enemy.
Q: Warlock the Undying
A: Hard to explain. It's Lich-like, but not undead it seems.
Q: Paladin Oath of the Crown
A: The new paladin oath is a straight up tank. They seem to have added a ton more detail for the paladin codes. Too much to go into here.
Q: Fighter Purple Dragon Knight
A:Party buffs/heals. Would be a good party leader out of combat as well.
Q: How do the Half elf and tiefling variants work?
A: Tiefling variants are pretty different. I'm not next to my book currently, but I believe there were three options. Half elf replaced the half elf skill dealy with a selection from the elf half. Like Drow magic replacing the skill selection for example.
Q: What does it say about Aasimar?
A: It basically just says, "See the DMG.
(I guess that makes Eldarin valid as well)
Edit 1: Did some cleaning, added cantrips and explanation that is not me giving the answers.