- Both Action Comics and Justice League are set at the "dawning of the age of superheroes," DC said. (But that dawn doesn't appear to be too long ago, since it's being reported that they will take place only five years in the past.)
- All other September titles will be taking place in DC's "contemporary times," unless it's a period piece, like Demon Knights, Jonah Hex or Legion of Super-Heroes.
I'm hoping that DC decides to use the "five years" rule for Legion. If there needs to be a team that needs to be de-aged a tad, it's them. You can have Garth & Imra still married in their early 20's, but have Cos and most of the rest of the team still in their late teens. (He was 14 when the Legion started. Do the math.)