Reboot to the Head

You may have read the reports by now, that, as of the end of Flashpoint on August 31, DC is relaunching its entire line-up in September, with 52 series all beginning with new first issues. Now that the can of worms has been opened and the beans are spilled (they're bean worms), news and speculation is rampant. What we actually know is very little except that the DCUniverse is getting overhauled, big time.

One possible scenario is Flashpoint could be rewriting history/continuity, so that things are somewhat the same, yet different, in many ways to be revealed. As such with the first issue of each title it's possible we might join a character in-progress, perhaps we know them well, perhaps we don't know them as well as we think we do, or perhaps we don't know them at all. Their pasts may be unclear but that will provide writers the abililty to keep the parts of the past they want and discard the others (though I would not want to be the editor responsible for keeping all the rewritten continuity straight). Hopefully writers will look forward, instead of back, for the most part. But, unlike the "Superboy-punch" of not so long ago, this won't be a means to escape explaining something away, but instead a means of ignoring it altogether. Think the JJ Abrams Star Trek film, how it managed to forge its own path to go forth without completely ignoring or invalidating the past Trek lore.

Another possible scenario is the "coincidence" of 52. I have to wonder if there's not some correlation between the relaunch and the 52 universes introduced in the weekly series of recent yore. Dwayne McDuffie, rest his soul, was a big champion for each title operating as its own stand-alone universe, in a sense, able to incorporate or ignore the "Shared Universe" at its own leisure but not beholden to it in any way, shape or form. McDuffie postulated that the only continuity that would matter for a title is its own continuity. To exemplify, McDuffie explains about guest-appearances:

Guest Shots are permissible, but they only affect the continuity of the book they appeared in. If Flash does a guest-shot in Green Lantern, [where] there's no Empire State Building .... [this] Flash sees nothing wrong with that. Moreover, back in the pages of The Flash, the crossover story never happened.

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To take his system even further, say if a creative team came aboard and wanted to completely reinvent the character or series, start at issue 1 with a whole new canon, they could. Much in the same way the Bond films work or even how characters like Batman get rebooted in cinema. Personally I think that each creative team should establish their character, their universe for the story they want to tell. If someone wants a ten year run on Batman, go for it, but then the next writer can take and leave what happened there in part or in total. The same as if another creator only wants to dabble in Blue Beetle's waters for a three issue arc, then give them a three issue series to do it in and reboot it again for the next writer.
The alternative to the "Mono-Earth" scenario would be each of these 52 series be their own universe, but part of a larger universe in such a way that, say, Green Lantern's book would have its own Flash, but if he wanted to cross over with the Justice League, he would need to dimension hop and ultimately there could conceivably be 52 iterations of each character? My brain hurts a little thinking about it that way.

But enough speculation on how it will play out, the other speculation is on what series will be involve and what it means for existing books.

Revealed:
Justice League written by Geoff Johns, illustrated by Jim Lee, with a "big seven" focus sort of like Morrison's JLA or the Justice League cartoon. Superman, Batman, Wonder Woman, Green Lantern, Aquaman, Flash, Cyborg. (Also, apparently, akin to Morrison's JLA, a sub-roster of 7 other heroes).

Hinted:
Superman and Action Comics (perhaps with the involvement of Morrison, George Perez and Rags Morales)
Wonder Woman (maintaining the new costume but distancing itself from the JMS character relaunch)
Adventure Comics (starring Deadman) (with the rumoured involvement of Gail Simone)
Batgirl (Barbara Gordon... so long Steph?)
Nightwing (also with the rumoured involvement of Simone)
Batwoman (it was likely delayed intentionally to coincide with the September relaunch)
Justice League International (as was promoted at the end of "Generation Lost")
"Team Lantern" - A team book featuring an ensemble of rainbow Lanterns
Green Lantern - Geoff Johns still involved
Aquaman - Also Johns with Ivan Reis
Hawkman with James Robinson and Philip Tan
Birds of Prey (Simone-less)
Teen Titans by Fabian Nicieza
Justice Society (new creative team)

Rumoured:
Firestorm
OMAC (with the involvement of Scott Kolins and/or Dan DiDio and Keith Giffen)
Legion Lost

No Mention, But Obviously:
Batman
Detective Comics
Robin
Green Arrow
Flash

A Good Chance Of:
Swamp Thing
Martian Manhunter
Legion of Super-Heroes (a title which could continue almost entirely unscathed)
Static (or Static Shock)
Supergirl

A Less Good Chance of:
Booster Gold
Blue Beetle solo series
Cyborg solo series
Superboy

Going Bye-Bye? :
Zatanna
Secret Six

I suspected that the lack of a letter column meant they were done for:
Xombi
T.H.U.N.D.E.R. Agents