Yesterday Microsoft announced that a Halo anime and a new Halo segment of Xbox Live were on the way. Today they topped that by releasing the first gameplay trailer for standalone expansion Halo 3: ODST.

In ODST, you play not as Master Chief but as an Orbital Drop Shock Trooper, an elite type of soldier who drops into hot zones from orbit via a special pod. What's sweet is you'll actually get to see your character dropping from orbit in first-person perspective. Seems something goes wrong with the drop though and you're separated from the rest of your team.

ODST will be released on September 22nd, 2009. Looks pretty good, though I'm sure a lot of folks will buy it primarily for the Halo: Reach beta voucher.