WHO IT PROBABLY WILL BE: Aquaman
WHO IT SHOULD BE: Wonder Woman
WHO I WANT IT TO BE: Green Arrow
In all seriousness, I don't want them to just say, "it's Aquaman." I know what I'm about to say is very obvious, but Superfriends may have been the most damaging thing to ever happen to the character in his history. Aquaman hasn't been a joke, "oh he's only effective underwater, and even then he's just going to summon whales," character in about 40 years. The ways he's been used in Justice League and Justice League Unlimited (and from what I know, I realize that's how Namor the Sub-Mariner, at his most heroic, is depicted) or at the very least Batman: The Brave and the Bold is how I've always thought he should be portrayed.
Personally I think it'd be a huge curveball if they either lied and reveal it as Wonder Woman in the book or if it ends up being Flash. Wondie just makes the most sense to be a lesbian. Living on an island full of smoking hot women who are all into bondage and that no man can ever visit? Come on, that just makes sense...in kind of a silly, comic book way, but baby steps. Oh wait, I take that back, they gave her Cassandra Sandsmark's backstory in the reboot. Yes, instead of the very good, "baby made of clay given life by the greek gods," backstory, they gave her the backstory of her former sidekick. If I were to go out on a limb and say, "this is who I think it should be," I think I'd go with Green Arrow. Personally I think permenantly ending any sort of romantic relationship between him and Black Canary would be a big help toward getting both characters back on track. You can jokingly have him flirt with Canary, I've got no problem with that, but really, no romantic stuff. Reason being, when was the last time Green Arrow was in a good comic? I'd guess back when they teamed him up with Hal Jordan. As a final note, I think getting Arrow's name back out there would not only be a good move, but a recognition move, especially since everyone's now pretty aware of Marvel's superhero who uses a bow and arrow as his primary weapon. [http://marvel.wikia.com/Clinton_Barton_(Earth-616)] Green Arrow is really not a hard concept to nail down to begin with, he's Robin Hood with Bruce Wayne's resources. Add in this, and you might actually have a really interesting character. Arrow also hasn't had a ton of exposure either and this might be good for his name recognition.