Apparently, Ray Park, the stunt man turned actor who played Darth Maul (his body anyway not his voice*) in The Phantom Menace and Toad in X-Men, will be playing “one of the colorful characters at the centre of the show's Carnivale-esque storyline. (My guess? He's the character described in the breakdowns as ‘Knife Thrower‘)” says EW’s Mike Ausiello.
Also, Deanne Bray (from The L Word) is “nearing a deal” to come on board for multiple episodes as “a deaf love interest for one of the main Heroes”.
* A special no prize to the first person to name the actor who supplied his voice (we were just too lazy to look up how to spell it)