Normally, I'm a fan of gritty realism, but for some reason, this trailer feels like it's trying too hard. Trying to smash "Halo" and "war movie" together in my head just winds up creating dissonance. Granted, it's not like Halo has been trying to be anything else in its entire run, but with this trailer, it seems like they're just suddenly trying to minimize the sci-fi aspects, to the point where in the medium switch (from video game to video) it feels like there was a genre switch too.
Actually, it strikes me that the trailer is probably targeted to those who haven't touched Halo in the past. The existing fanbase of loyal frat'tards are going to be onboard with ODST, regardless of marketing because, "It's Halo, brah! And they, like, moved the HUD icons around and stuff, so innovation!" Microsoft may be taking a stab at expanding the audience, by making a late grab for BSG's coattails.
Had I never played Halo before, I'd probably be impressed. Had the trailer not had a Halo logo at the end and varied the costume design just enough to separate it from the franchise, I'd also have probably enjoyed it. Unfortunately, I have a notion of what Halo's about, and this trailer is so at odds with that notion that I can't really see past the conflict or identify it as anything but a mildly deceptive marketing ploy.