I'm just hoping they get away from using the Elites as antagonists. After the big rebellion at the end of Halo 3, it felt like a misfire to be fighting against them again in Halo 4, even if it was an offshoot group/cult/whatever. Also, caught that Cortana hint at the end of the trailer. Another misfire from H4; not necessarily the fact that she died, but how she died/saved Master Chief. Just weird. Also weird that they kill her off right before they launch the Cortana app. It looks like somebody thought the same thing, and now they'll try to put her back in the game somehow. Unless she got absorbed into forerunner tech and becomes some kind of mad tech goddess. Then I approve.