Bungie has revealed that there are no Elites in Halo 3: ODST because the new villain doesn't like them.
Elites - think Arbiter from Halo 3 - are viewed by new baddie the Prophet of Truth as being "too splintered by heresy and derision". And he knows his faith will be returned ten-fold by the eager Brutes, making them the perfect pawns to carry out a dastardly plan.
There's a more detailed background on the Bungie site, but those yet to play or finish Halo 2 should beware: spoilers be here.
Halo 3: ODST acts as a prequel to Halo 3, and should offer "hours of new campaign" gameplay that represents "a lot of value", according to Bungie. Also, the prequel will be a standalone product, meaning there's no need to own Halo 3.
Halo 3: ODST will launch exclusively for Xbox 360 this autumn.
Head over to our Halo 3: ODST gamepage for more information.