Second best in series IMO.
But it did feel alot like Halo: Combat evolved to me and less like Halo 3 or Halo 2 (halo 3 was such a disapointment to me). So overall I enjoyed the campaign and Firefight is alot of fun with a few friends so if you enjoyed the first game you should enjoy this one, but thats my opinion of course.
The voice actors are mainly from the tv series ''Firefly'' which I never actually watched but I enjoyed there performances, expecially Mickey he was pretty good, seemed happy to be killing aliens.
My favourite weapon of course is the automag, feels alot like the classic halo pistol just not as powerful, I personally didnt miss duel wielding never cared for it in the first place so was glad to see it wasnt on the game. Couldnt understand how a helljumper could run around with a turret though, I realize its game mechanics to make it more fun but none of the ODST's seem strong enough to handle a big minigun on the run.... possibly Dutch but thats really about it.
Still slightly disapointed they didnt go for a more stealthy game due to the fact ODST's aka Helljumper's usually use stealth or shock tactics when in a highly dangerous situation since if your shot your dead period.
Still enjoyed it, if you enjoy the halo games you should enjoy it if not really doesnt matter to me its your call.