As the title says, this is speculation. Suckily, all of this comes from non-story sources. But piecing together some marketing statements, it seems pretty ovious.
So a January 52 will have Supernova reveal himself."Week 35...the reveal of Supernova will deepen his mysteries even further."
"Determined to rebuild the Justice Society, founding members Green Lantern, Flash and Wildcat initiate an unprecedented recruitment program, tracking the bloodlines of heroes across the world and bringing in the new Starman, Damage, Liberty Belle and more!...JSA #1 comes out December 6th."
http://www.newsarama.com/dcnew/JSA/01/JSA01_pre.htmlIn december we'll find out that Supernova is the new Starman, who looks like the Kingdom Come Starman (but who isn't.)"Q: In which issue will you reveal Supernova's identity?!
SW: Issue #1. But Iím not saying issue #1 of what."
So now the question becomes: who is this new Starman?