Initial reports indicated long-time Batman voice actor Conroy wasn't in Origins. He then announced at the recent Dallas Comic Con that he'd been working on "the next Arkham" game. Shortly after, Craig Smith was officially unveiled as Origins' younger Batman, leading to speculation Conroy might be involved in some kind of retrospective role.
However, it now emerges Conroy was apparently talking about another Arkham game in development, perhaps at series dev Rocksteady Studios - Warner Bros. Montreal is the studio behind Origins.
That would seem to be backed up by Spong's report from last month, which noted a Twitter account ascribed to Conroy tweeted "Confusion in Dallas! I am in new ARKHAM GAME coming soon, NOT ARKHAM ORIGINS coming this fall." The tweet was deleted shortly after being posted - we're not sure if the world's greatest detective is needed for this one.