It's not officially confirmed, but there's some strong unofficial evidence. Plus, c'mon, it's Dick.

See, I like Grant Morrison, but only some of his stuff. He can get too weird for his own good, but when he's on he is on. ASS was excellent, We3, his Justice League, heck really everything he's done for Vertigo. (Save Invisibles, because I never could get into that.) His run on Batman, though, I had some trouble with.