Multiversity Spoilers Ahead. Read at your own risk.
I don't think we've restarted this thread since the forums rebooted. With Morrison just having released the Multiversity map, we now have insight into what the post-Flashpoint 52 worlds are. It seems that so far, these are pretty similar to the post-Infinite Crisis worlds, but they've been "Nu-52ified," or as Grant Morrison puts it, "they now look like they're drawn by Jim Lee." In the list below, I've included what limited identifiers we had from series such as Countdown, but keep in mind that many of these may have changed since Flashpoint.
I have only identified worlds which Morrison has affirmatively said "this is Earth-10" or whatever. As more worlds become identified, I'll change this list. So, here goes:
0 - New Earth; home of the Justice League.
- Trinity: Superman (Kal-El/Clark Kent), Batman (Bruce Wayne), Wonder Woman (Diana)
1 - Earth One; based on the OGN line.
- Trinity: Superman (Kal-El/Clark Kent), Batman (Bruce Wayne), Wonder Woman (Diana)
2 - Earth-2, home of the Justice Society.
- Trinity: Superman (Val Zod), Batman (Thomas Wayne, Sr.), Fury
3 - Earth-3; home of the Crime Syndicate and the Anti-Monitor. Destroyed.
- Trinity: Ultraman (Kal-Il/Clark Kent), Owlman (Thomas Wayne, Jr.), Superwoman (Lois Lane)
4 - Charlton Earth; home of the Pax Americana.
- Trinity Analogues: Captain Atom (Nathaniel Adam), Question (Victor Sage), Nightshade (Eve Eden)
5 - Thunderworld; home of the Fawcett characters (the Marvels, Dr. Sivana, etc.) .
- Trinity Analogues: Captain Marvel (Billy Batson)
6 - The "Just Imagine Stan Lee Creating..." universe.
- Trinity: Superman (Salden), Batman (Wayne Williams), Wonder Woman (Maria Mendoza)
7 - "Essential Major Comics" Earth (an ersatz Ultimate Marvel with hints of Hellboy) (see Earth-8); home of Thunderer. This world has been heavily damaged following the Gentry's attack.
- Trinity: Unknown (Thunderer may be a Superman analogue; Walkurye seems to be an Angela/Wonder Woman combination)
8 - "Major Comics" Earth; an ersatz Marvel universe and home of the Retaliators.
- Trinity: Unknown (possibly Hyperius and Major Max)
9 - Tangent Earth.
- Trinity: Superman (Harvey Dent), Batman (Sir William), Wonder Woman (Wanda). (Note: The Atom might be a better Superman analogue here.)
10 - Nazi Earth; home of the New Reichsmen and the Freedom Fighters.
- Trinity: Overman, Leatherwing, Brunhilde
11 - Genderswap-Earth; home of the Justice Guild.
- Trinity: Superwoman (Laurel), Batwoman, Wonderous Man (Dane)
12 - "Beyond"-Earth; home of the Justice League Beyond. (Presumably its past is or resembles the DCAU.)
- Trinity: Superman (Clark Kent), Batman (Terry McGuinness), Wonder Woman (Diana)
13 - Gothic Earth; home of the League of Shadows. Pre-Nu52, this was a "Vertigo-like" Earth.
- Trinity: Superdemon (Jason Blood)
14 - An unknown (dual?) Earth.
- Trinity: Unknown
15 - Utopian-Earth. Destroyed.
- Trinity: Currently none (pre-Nu52, Superman (Zod), Batman (Jason Todd), Wonder Woman (Donna Troy))
16 - Earth-Me; home of the Just
- Trinity: Superman (Chris Kent), Batman (Damian Wayne), Wonder Woman (Artemis)
17 - Post-Atomic Holocaust Earth; home of the Atomic Knights of Justice.
- Trinity: Superman analogue uncertain, Batman (Bruce Wayne), Wonder Woman (Unknown)
18 - Old West Earth; home of the Justice Riders.
- Trinity: Super Chief (Saganowana), El Diablo, Madame .44
19 - Victorian-Earth; based on Gotham by Gaslight and Wonder Woman: Amazonia.
- Trinity: Batman (Bruce Wayne); Wonder Woman (Diana) (Superman analogue uncertain).
20 - Pulp-Earth; home of the Society of Super-Heroes.
- Trinity: Unclear. (Could be any of the SOS members; a "Bat-Man" is known to be on this world)
21 - DC: The New Frontier; home of the Justice League of America.
- Trinity: Superman (Clark Kent), Batman (Bruce Wayne), Wonder Woman (Diana)
22 - Kingdom Come; home of the Justice League.
- Trinity: Superman (Clark Kent), Batman (Bruce Wayne), Wonder Woman (Diana)
23 - Black-Earth; home of black versions of the New Earth heroes
- Trinity: Superman (Kal-El/President Calvin Ellis), Batman (Bruce Wayne), Wonder Woman (Nubia)
24 - An "Unknown Earth."
- Trinity: Unknown.
25 - An "Unknown Earth."
- Trinity: Unknown.
26 - "Earth C"; home of the Zoo Crew.
- Trinity: Captain Carrot (Rodney Rabbit), American Eagle (Johnny Jingo), Yankee Poodle (Rova Barkitt)
27 - An "Unknown Earth."
- Trinity: Unknown.
28 - An "Unknown Earth."
- Trinity: Unknown.
Bizarro World - 29; away of Unjustice League of Unamerica.
- No Am Trinity: Unknown (Bizarro), Unknown (Batzarro), Unknown (Bizarro Wonder Woman)
30 - Soviet-Earth; inspired by Superman: Red Son.
- Trinity: Superman (Kal-El/name unknown), Batman (Unknown), Wonder Woman (Diana)
31 - Pirate World based on Detective Comics Annual #9. Much to our confusion, this is no longer the Frank Millerverse.
- Trinity: Unidentified Superman; Leatherwing; Unidentified Wonder Woman
32 - Earth-Mashup (based on Batman: In Darkest Knight); home of the Justice Titans.
- Trinity: SuperMartian (unknown), Bat Lantern (Bruce Wayne), WonderHawk (Diana)
33 - "Earth-Prime"--the "real world."
- Trinity: Unknown--we likely don't have one.
34 - Earth-Cosmoville (an Astro City analogue); home of the Light Brigade.
- Trinity: Savior, Stingray (Bruce Wayne), Herculina
35 - Earth-Pseudoverse (an Extreme Comics analogue); home of the Super-Americans.
- Trinity: Supremo, the Owl (Bruce Wayne), and Majesty
36 - A Big Bang Comics analogue; home of the Justice 9.
- Trinity: Optiman (deceased), Iron Knight (Bruce Wayne), War-Woman
37 - A "Howard Chaykin" universe based on Batman: Thrillkiller.
- Trinity: Unknown except for Batgirl (Barbara Gordon)
38 - John Byrne's Superman/Batman: Generations.
- Trinity: Superman (Kal-El/Clark Kent), Batman (Bruce Wayne), Wonder Woman (Diana).
39 - A "Wally Wood" sci-fi world; home of the Agents of W.O.N.D.E.R.
- Trinity: Unclear.
40 - Dark-Pulp Earth; home of the Society of Super Villains.
- Trinity: Unknown,
41 - An ersatz "Image Comics"-Earth.
- Trinity: Superman analogue unclear, Scorpion (Bruce Wayne), Vague
42 - Chibi-Earth; home of the Little Leaguers.
- Trinity: Chibi versions of Superman, Batman (Dick Grayson), and Wonder Woman
43 - Vampire-Earth; home of the Blood League. Inspired by Batman & Dracula: Red Rain.
- Trinity: Ultraman, Batman (Bruce Wayne), Wonder Woman (Diana)
44 - Robot Earth; home of the Metal League.
- Trinity: Gold Superman, Iron Batman, and Platinum Wonder Woman
45 - Corporate-Earth from Action Comics #9.
- Trinity: Superdoom (created by Clark Kent)
46 - An "Unknown Earth."
- Trinity: Unknown.
47 - Dreamworld; home of the Love Syndicate.
- Trinity: Sunshine Superman, Shooting Star (Bruce Wayne)
48 - Warworld (an "Alan Moore" Universe based on Top Ten and Twilight of the Superheroes); home of Lord Volt and Lady Quark.
- Trinity: Unknown (probably includes Lord Volt and Lady Quark)
49 - An "Unknown Earth."
- Trinity: Unknown.
50 - Justice Lords Earth; home of the Justice Lords Beyond.
- Trinity: Lord Superman (Kal-El/Clark Kent), Lord Batman (Bruce Wayne), Lord Wonder Woman (Diana)
51 - "Great Disaster Earth" (or the "Jack Kirby" Earth); home of Kamandi
- Trinity: Unknown.
Blood Moon: Brainiac's home where he holds cities taken from Earths no longer in existence.
Wonderworld: A futuristic world of colossal superheroes used in Morrison's JLA: Rock of Ages story.
Kwyzz: A world of radio-beings from Morrison's Flash run.