Back when we saw DC Universe Online at Sony Online Entertainment’s office in Austin, TX, they weren’t ready to tell us who they’d lined up for voice acting. Today, just one day ahead of San Diego Comic Con 2010, they’re ready to tell us who they’ve got.

The big ticket actors are Mark Hamill and Kevin Conroy in their traditional roles of The Joker and Batman, which they first filled in the 1990s’ Batman: The Animated Series and later returned to for Rocksteady Studios’ massively successful Batman: Arkham Asylum on PlayStation 3 and Xbox 360.

Adam Baldwin, meanwhile, will play the voice of Superman in DC Universe Online. Gina Torres will play Superwoman, reprising her role from the animated feature Justice League: Crisis on Two Earths. James Marsters is lined up to play Lex Luthor while Michelle Forbes takes on the role of Circe, rounding out the bad guy lineup.

No word yet on who will play Catwoman, Zatanna Zatarra, or Martian Manhunter. But, hey, DCUO has to save something to announce at Comic Con proper, right?

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