There's a small interview with Morisson in the latest issue of Wizard
From the gist of the interview I got the following. Yes Damien is Bruce's own flesh and blood. He also says that he is interested in stories of how f*ck ups (yes his words) grow up to redeem themselves later on. So I guess if Morisson has his druthers Damien the demon will grow up to be a hero. Little Damien is supposed to be angry and confused. But now that he is with his very cool Dad (Batman) he will grow up to be a fine upstanding citizen.
And for those of us who were puzzled by the incongruity of events that took place between SOD and what's in Morisson's work.Morisson admits that he went by his memmories of SOD, he did not follow it when he was writing.
He claims that Superboy's 'retcon' punch has saved his ass.