Popular Mechanics has an interesting article about how Halo 3: ODST came to pass. The article is right that ODST did a great job of creating a new game with Halo 3 gameplay but a very different feel.
But they also make a mistake by crediting ODST with the idea of rapidly developing a new story on an existing engine. The idea goes back at least as far as Half-Life 2 Episode One (great game, awful name). And it’s been used in several shooters since, including GRAW 2 and Rainbow Six Vegas 2.
I also think the staying power of ODST isn’t going to be in the new campaign — which is actually a little too short — but the new “firefight” mode, which pits a team of human players against wave after wave of AI attackers. Firefight isn’t original either. It’s a copy of the “Horde” mode in Gears of War 2, but I think it’s better executed than the Gears of War version.
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