I prefer it when companies roll out their games on their own terms, rather than tethering them to some awards or convention show bonanza. Would be great if they settle in and decide they're ready and just crank out an insane trailer. I was going back through the Skyrim threads the other night and was reminded how great Bethesda handled the build up to and release of their
first gameplay trailer.
First footage was late February, game comes out in November. Assuming we see something in the first month or two of next year, Halo 4 is on a similar time frame (even assuming a September release).