In the trailer for Halo ODST they actually use some real scenes by actors and not just animation, really cool.
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About 2.5 million people have bought the latest Halo 3: ODST game ($60, for Xbox 360) since it was released two weeks ago, a nice reception for a game that doesn't star Halo main man, the Master Chief. Instead, players control a squad of futuristic special forces known as Orbital Drop Shock Troopers (ODSTs) deployed to fight off the enemy forces of The Covenant attacking Earth. Ref. Source 7
I've played the game at my daughter's house a little bit.
It is very nice to play. The weapons are pretty much the same as in Halo 3. There are a few differences, including a couple of enhancements that the marines have that the Master Chief did not have. It has a strong built-in map feature, with the ability to pace waypoints to help guide the player. It also has some in-game mini-plays that the player can access, that are interesting but not necessary to the story.
The feature that my sons and son-in-law really like is a "Firefight" where two players fight against waves of enemy combatants. A couple of days ago, they brought two XBox 360's to our house, connected them, and four of them played Firefight at once. They sure seemed to have a lot of fun.
I tend to play the campaigns on these games, so that I learn all of the different weapons well. I haven't played multiplayer on either Halo 3 or ODST yet, but I am sure I will one day soon.
Overall, I really like this game.
The meaning of "ODST" itself stands for Orbital Drop Shock Trooper.