From Joystiq:
Re: Halo ODST (coming late September):
Sci-fi nerds are in for a real treat, as Fillion is joined by some other space-faring actors, including Firefly co-stars Adam Baldwin and Alan Tudyk as Dutch and Mickey, respectively. And there’s everyone’s favorite Cylon, Tricia Helfer as Dare. The Joystiq staff is fairly certain that Romeo is played by Nolan “Nathan Drake” North, too.
Sounds like some pretty sweet voice acting. Who’s gonna come over and watch me play? (Actually playing with me is even better, but I’ll take what I can get!)

I’d probably be game for some Firefight at the end of September… but I do want to go through ODST’s campaign solo for the first run, just so I can absorb all the ambiance.
— Steve also has a painfully slow (or so he’s told) play style in these things… but it looks like caution will win over audacity when going up against Brutes, so maybe it’ll work out after all.